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/cdev.h>
22 #include <linux/poll.h>
23 #include <linux/mei.h>
24 #include <linux/mei_cl_bus.h>
33 extern const uuid_le mei_amthif_guid;
35 #define MEI_RD_MSG_BUF_SIZE (128 * sizeof(u32))
38 * Number of Maximum MEI Clients
40 #define MEI_CLIENTS_MAX 256
43 * maximum number of consecutive resets
45 #define MEI_MAX_CONSEC_RESET 3
48 * Number of File descriptors/handles
49 * that can be opened to the driver.
51 * Limit to 255: 256 Total Clients
52 * minus internal client for MEI Bus Messages
54 #define MEI_MAX_OPEN_HANDLE_COUNT (MEI_CLIENTS_MAX - 1)
58 MEI_FILE_INITIALIZING = 0,
61 MEI_FILE_DISCONNECTING,
62 MEI_FILE_DISCONNECT_REPLY,
63 MEI_FILE_DISCONNECT_REQUIRED,
64 MEI_FILE_DISCONNECTED,
67 /* MEI device states */
69 MEI_DEV_INITIALIZING = 0,
78 const char *mei_dev_state_str(int state);
83 MEI_IAMTHIF_FLOW_CONTROL,
85 MEI_IAMTHIF_READ_COMPLETE
88 enum mei_file_transaction_states {
98 * enum mei_cb_file_ops - file operation associated with the callback
100 * @MEI_FOP_WRITE: write
101 * @MEI_FOP_CONNECT: connect
102 * @MEI_FOP_DISCONNECT: disconnect
103 * @MEI_FOP_DISCONNECT_RSP: disconnect response
104 * @MEI_FOP_NOTIFY_START: start notification
105 * @MEI_FOP_NOTIFY_STOP: stop notification
107 enum mei_cb_file_ops {
112 MEI_FOP_DISCONNECT_RSP,
113 MEI_FOP_NOTIFY_START,
118 * Intel MEI message data struct
120 struct mei_msg_data {
125 /* Maximum number of processed FW status registers */
126 #define MEI_FW_STATUS_MAX 6
127 /* Minimal buffer for FW status string (8 bytes in dw + space or '\0') */
128 #define MEI_FW_STATUS_STR_SZ (MEI_FW_STATUS_MAX * (8 + 1))
132 * struct mei_fw_status - storage of FW status data
134 * @count: number of actually available elements in array
135 * @status: FW status registers
137 struct mei_fw_status {
139 u32 status[MEI_FW_STATUS_MAX];
143 * struct mei_me_client - representation of me (fw) client
145 * @list: link in me client list
146 * @refcnt: struct reference count
147 * @props: client properties
148 * @client_id: me client id
149 * @mei_flow_ctrl_creds: flow control credits
150 * @connect_count: number connections to this client
151 * @bus_added: added to bus
153 struct mei_me_client {
154 struct list_head list;
156 struct mei_client_properties props;
158 u8 mei_flow_ctrl_creds;
167 * struct mei_cl_cb - file operation callback structure
169 * @list: link in callback queue
170 * @cl: file client who is running this operation
171 * @fop_type: file operation type
172 * @buf: buffer for data associated with the callback
173 * @buf_idx: last read index
174 * @fp: pointer to file structure
175 * @status: io status of the cb
176 * @internal: communication between driver and FW flag
177 * @completed: the transfer or reception has completed
180 struct list_head list;
182 enum mei_cb_file_ops fop_type;
183 struct mei_msg_data buf;
185 const struct file *fp;
192 * struct mei_cl - me client host representation
193 * carried in file->private_data
195 * @link: link in the clients list
196 * @dev: mei parent device
197 * @state: file operation state
198 * @tx_wait: wait queue for tx completion
199 * @rx_wait: wait queue for rx completion
200 * @wait: wait queue for management operation
201 * @ev_wait: notification wait queue
202 * @ev_async: event async notification
203 * @status: connection status
204 * @me_cl: fw client connected
205 * @host_client_id: host id
206 * @mei_flow_ctrl_creds: transmit flow credentials
207 * @timer_count: watchdog timer for operation completion
208 * @reserved: reserved for alignment
209 * @notify_en: notification - enabled/disabled
210 * @notify_ev: pending notification event
211 * @writing_state: state of the tx
212 * @rd_pending: pending read credits
213 * @rd_completed: completed read
215 * @cldev: device on the mei client bus
218 struct list_head link;
219 struct mei_device *dev;
220 enum file_state state;
221 wait_queue_head_t tx_wait;
222 wait_queue_head_t rx_wait;
223 wait_queue_head_t wait;
224 wait_queue_head_t ev_wait;
225 struct fasync_struct *ev_async;
227 struct mei_me_client *me_cl;
229 u8 mei_flow_ctrl_creds;
234 enum mei_file_transaction_states writing_state;
235 struct list_head rd_pending;
236 struct list_head rd_completed;
238 struct mei_cl_device *cldev;
242 * struct mei_hw_ops - hw specific ops
244 * @host_is_ready : query for host readiness
246 * @hw_is_ready : query if hw is ready
247 * @hw_reset : reset hw
248 * @hw_start : start hw after reset
249 * @hw_config : configure hw
251 * @fw_status : get fw status registers
252 * @pg_state : power gating state of the device
253 * @pg_in_transition : is device now in pg transition
254 * @pg_is_enabled : is power gating enabled
256 * @intr_clear : clear pending interrupts
257 * @intr_enable : enable interrupts
258 * @intr_disable : disable interrupts
260 * @hbuf_free_slots : query for write buffer empty slots
261 * @hbuf_is_ready : query if write buffer is empty
262 * @hbuf_max_len : query for write buffer max len
264 * @write : write a message to FW
266 * @rdbuf_full_slots : query how many slots are filled
268 * @read_hdr : get first 4 bytes (header)
269 * @read : read a buffer from the FW
273 bool (*host_is_ready)(struct mei_device *dev);
275 bool (*hw_is_ready)(struct mei_device *dev);
276 int (*hw_reset)(struct mei_device *dev, bool enable);
277 int (*hw_start)(struct mei_device *dev);
278 void (*hw_config)(struct mei_device *dev);
281 int (*fw_status)(struct mei_device *dev, struct mei_fw_status *fw_sts);
282 enum mei_pg_state (*pg_state)(struct mei_device *dev);
283 bool (*pg_in_transition)(struct mei_device *dev);
284 bool (*pg_is_enabled)(struct mei_device *dev);
286 void (*intr_clear)(struct mei_device *dev);
287 void (*intr_enable)(struct mei_device *dev);
288 void (*intr_disable)(struct mei_device *dev);
290 int (*hbuf_free_slots)(struct mei_device *dev);
291 bool (*hbuf_is_ready)(struct mei_device *dev);
292 size_t (*hbuf_max_len)(const struct mei_device *dev);
294 int (*write)(struct mei_device *dev,
295 struct mei_msg_hdr *hdr,
298 int (*rdbuf_full_slots)(struct mei_device *dev);
300 u32 (*read_hdr)(const struct mei_device *dev);
301 int (*read)(struct mei_device *dev,
302 unsigned char *buf, unsigned long len);
306 void mei_cl_bus_rescan(struct mei_device *bus);
307 void mei_cl_bus_rescan_work(struct work_struct *work);
308 void mei_cl_bus_dev_fixup(struct mei_cl_device *dev);
309 ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
311 ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length);
312 bool mei_cl_bus_rx_event(struct mei_cl *cl);
313 bool mei_cl_bus_notify_event(struct mei_cl *cl);
314 void mei_cl_bus_remove_devices(struct mei_device *bus);
315 int mei_cl_bus_init(void);
316 void mei_cl_bus_exit(void);
319 * enum mei_pg_event - power gating transition events
321 * @MEI_PG_EVENT_IDLE: the driver is not in power gating transition
322 * @MEI_PG_EVENT_WAIT: the driver is waiting for a pg event to complete
323 * @MEI_PG_EVENT_RECEIVED: the driver received pg event
324 * @MEI_PG_EVENT_INTR_WAIT: the driver is waiting for a pg event interrupt
325 * @MEI_PG_EVENT_INTR_RECEIVED: the driver received pg event interrupt
330 MEI_PG_EVENT_RECEIVED,
331 MEI_PG_EVENT_INTR_WAIT,
332 MEI_PG_EVENT_INTR_RECEIVED,
336 * enum mei_pg_state - device internal power gating state
338 * @MEI_PG_OFF: device is not power gated - it is active
339 * @MEI_PG_ON: device is power gated - it is in lower power state
346 const char *mei_pg_state_str(enum mei_pg_state state);
349 * struct mei_device - MEI private device struct
351 * @dev : device on a bus
352 * @cdev : character device
353 * @minor : minor number allocated for device
355 * @write_list : write pending list
356 * @write_waiting_list : write completion list
357 * @ctrl_wr_list : pending control write list
358 * @ctrl_rd_list : pending control read list
360 * @file_list : list of opened handles
361 * @open_handle_count: number of opened handles
363 * @device_lock : big device lock
364 * @timer_work : MEI timer delayed work (timeouts)
366 * @recvd_hw_ready : hw ready message received flag
368 * @wait_hw_ready : wait queue for receive HW ready message form FW
369 * @wait_pg : wait queue for receive PG message from FW
370 * @wait_hbm_start : wait queue for receive HBM start message from FW
372 * @reset_count : number of consecutive resets
373 * @dev_state : device state
374 * @hbm_state : state of host bus message protocol
375 * @init_clients_timer : HBM init handshake timeout
377 * @pg_event : power gating event
378 * @pg_domain : runtime PM domain
380 * @rd_msg_buf : control messages buffer
381 * @rd_msg_hdr : read message header storage
383 * @hbuf_depth : depth of hardware host/write buffer is slots
384 * @hbuf_is_ready : query if the host host/write buffer is ready
386 * @version : HBM protocol version in use
387 * @hbm_f_pg_supported : hbm feature pgi protocol
388 * @hbm_f_dc_supported : hbm feature dynamic clients
389 * @hbm_f_dot_supported : hbm feature disconnect on timeout
390 * @hbm_f_ev_supported : hbm feature event notification
391 * @hbm_f_fa_supported : hbm feature fixed address client
392 * @hbm_f_ie_supported : hbm feature immediate reply to enum request
394 * @me_clients_rwsem: rw lock over me_clients list
395 * @me_clients : list of FW clients
396 * @me_clients_map : FW clients bit map
397 * @host_clients_map : host clients id pool
399 * @allow_fixed_address: allow user space to connect a fixed client
400 * @override_fixed_address: force allow fixed address behavior
402 * @amthif_cmd_list : amthif list for cmd waiting
403 * @iamthif_fp : file for current amthif operation
404 * @iamthif_cl : amthif host client
405 * @iamthif_current_cb : amthif current operation callback
406 * @iamthif_open_count : number of opened amthif connections
407 * @iamthif_stall_timer : timer to detect amthif hang
408 * @iamthif_state : amthif processor state
409 * @iamthif_canceled : current amthif command is canceled
411 * @reset_work : work item for the device reset
412 * @bus_rescan_work : work item for the bus rescan
414 * @device_list : mei client bus list
415 * @cl_bus_lock : client bus list lock
417 * @dbgfs_dir : debugfs mei root directory
419 * @ops: : hw specific operations
420 * @hw : hw specific data
427 struct mei_cl_cb write_list;
428 struct mei_cl_cb write_waiting_list;
429 struct mei_cl_cb ctrl_wr_list;
430 struct mei_cl_cb ctrl_rd_list;
432 struct list_head file_list;
433 long open_handle_count;
435 struct mutex device_lock;
436 struct delayed_work timer_work;
440 * waiting queue for receive message from FW
442 wait_queue_head_t wait_hw_ready;
443 wait_queue_head_t wait_pg;
444 wait_queue_head_t wait_hbm_start;
449 unsigned long reset_count;
450 enum mei_dev_state dev_state;
451 enum mei_hbm_state hbm_state;
452 u16 init_clients_timer;
455 * Power Gating support
457 enum mei_pg_event pg_event;
459 struct dev_pm_domain pg_domain;
460 #endif /* CONFIG_PM */
462 unsigned char rd_msg_buf[MEI_RD_MSG_BUF_SIZE];
469 struct hbm_version version;
470 unsigned int hbm_f_pg_supported:1;
471 unsigned int hbm_f_dc_supported:1;
472 unsigned int hbm_f_dot_supported:1;
473 unsigned int hbm_f_ev_supported:1;
474 unsigned int hbm_f_fa_supported:1;
475 unsigned int hbm_f_ie_supported:1;
477 struct rw_semaphore me_clients_rwsem;
478 struct list_head me_clients;
479 DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX);
480 DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
482 bool allow_fixed_address;
483 bool override_fixed_address;
485 /* amthif list for cmd waiting */
486 struct mei_cl_cb amthif_cmd_list;
487 /* driver managed amthif list for reading completed amthif cmd data */
488 const struct file *iamthif_fp;
489 struct mei_cl iamthif_cl;
490 struct mei_cl_cb *iamthif_current_cb;
491 long iamthif_open_count;
492 u32 iamthif_stall_timer;
493 enum iamthif_states iamthif_state;
494 bool iamthif_canceled;
496 struct work_struct reset_work;
497 struct work_struct bus_rescan_work;
499 /* List of bus devices */
500 struct list_head device_list;
501 struct mutex cl_bus_lock;
503 #if IS_ENABLED(CONFIG_DEBUG_FS)
504 struct dentry *dbgfs_dir;
505 #endif /* CONFIG_DEBUG_FS */
508 const struct mei_hw_ops *ops;
509 char hw[0] __aligned(sizeof(void *));
512 static inline unsigned long mei_secs_to_jiffies(unsigned long sec)
514 return msecs_to_jiffies(sec * MSEC_PER_SEC);
518 * mei_data2slots - get slots - number of (dwords) from a message length
519 * + size of the mei header
521 * @length: size of the messages in bytes
523 * Return: number of slots
525 static inline u32 mei_data2slots(size_t length)
527 return DIV_ROUND_UP(sizeof(struct mei_msg_hdr) + length, 4);
531 * mei_slots2data - get data in slots - bytes from slots
533 * @slots: number of available slots
535 * Return: number of bytes in slots
537 static inline u32 mei_slots2data(int slots)
543 * mei init function prototypes
545 void mei_device_init(struct mei_device *dev,
546 struct device *device,
547 const struct mei_hw_ops *hw_ops);
548 int mei_reset(struct mei_device *dev);
549 int mei_start(struct mei_device *dev);
550 int mei_restart(struct mei_device *dev);
551 void mei_stop(struct mei_device *dev);
552 void mei_cancel_work(struct mei_device *dev);
555 * MEI interrupt functions prototype
558 void mei_timer(struct work_struct *work);
559 int mei_irq_read_handler(struct mei_device *dev,
560 struct mei_cl_cb *cmpl_list, s32 *slots);
562 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list);
563 void mei_irq_compl_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list);
566 * AMTHIF - AMT Host Interface Functions
568 void mei_amthif_reset_params(struct mei_device *dev);
570 int mei_amthif_host_init(struct mei_device *dev, struct mei_me_client *me_cl);
572 int mei_amthif_read(struct mei_device *dev, struct file *file,
573 char __user *ubuf, size_t length, loff_t *offset);
575 unsigned int mei_amthif_poll(struct mei_device *dev,
576 struct file *file, poll_table *wait);
578 int mei_amthif_release(struct mei_device *dev, struct file *file);
580 int mei_amthif_write(struct mei_cl *cl, struct mei_cl_cb *cb);
581 int mei_amthif_run_next_cmd(struct mei_device *dev);
582 int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
583 struct mei_cl_cb *cmpl_list);
585 void mei_amthif_complete(struct mei_cl *cl, struct mei_cl_cb *cb);
586 int mei_amthif_irq_read_msg(struct mei_cl *cl,
587 struct mei_msg_hdr *mei_hdr,
588 struct mei_cl_cb *complete_list);
589 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots);
592 * Register Access Function
596 static inline void mei_hw_config(struct mei_device *dev)
598 dev->ops->hw_config(dev);
601 static inline enum mei_pg_state mei_pg_state(struct mei_device *dev)
603 return dev->ops->pg_state(dev);
606 static inline bool mei_pg_in_transition(struct mei_device *dev)
608 return dev->ops->pg_in_transition(dev);
611 static inline bool mei_pg_is_enabled(struct mei_device *dev)
613 return dev->ops->pg_is_enabled(dev);
616 static inline int mei_hw_reset(struct mei_device *dev, bool enable)
618 return dev->ops->hw_reset(dev, enable);
621 static inline int mei_hw_start(struct mei_device *dev)
623 return dev->ops->hw_start(dev);
626 static inline void mei_clear_interrupts(struct mei_device *dev)
628 dev->ops->intr_clear(dev);
631 static inline void mei_enable_interrupts(struct mei_device *dev)
633 dev->ops->intr_enable(dev);
636 static inline void mei_disable_interrupts(struct mei_device *dev)
638 dev->ops->intr_disable(dev);
641 static inline bool mei_host_is_ready(struct mei_device *dev)
643 return dev->ops->host_is_ready(dev);
645 static inline bool mei_hw_is_ready(struct mei_device *dev)
647 return dev->ops->hw_is_ready(dev);
650 static inline bool mei_hbuf_is_ready(struct mei_device *dev)
652 return dev->ops->hbuf_is_ready(dev);
655 static inline int mei_hbuf_empty_slots(struct mei_device *dev)
657 return dev->ops->hbuf_free_slots(dev);
660 static inline size_t mei_hbuf_max_len(const struct mei_device *dev)
662 return dev->ops->hbuf_max_len(dev);
665 static inline int mei_write_message(struct mei_device *dev,
666 struct mei_msg_hdr *hdr, void *buf)
668 return dev->ops->write(dev, hdr, buf);
671 static inline u32 mei_read_hdr(const struct mei_device *dev)
673 return dev->ops->read_hdr(dev);
676 static inline void mei_read_slots(struct mei_device *dev,
677 unsigned char *buf, unsigned long len)
679 dev->ops->read(dev, buf, len);
682 static inline int mei_count_full_read_slots(struct mei_device *dev)
684 return dev->ops->rdbuf_full_slots(dev);
687 static inline int mei_fw_status(struct mei_device *dev,
688 struct mei_fw_status *fw_status)
690 return dev->ops->fw_status(dev, fw_status);
693 bool mei_hbuf_acquire(struct mei_device *dev);
695 bool mei_write_is_idle(struct mei_device *dev);
697 void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr);
699 #if IS_ENABLED(CONFIG_DEBUG_FS)
700 int mei_dbgfs_register(struct mei_device *dev, const char *name);
701 void mei_dbgfs_deregister(struct mei_device *dev);
703 static inline int mei_dbgfs_register(struct mei_device *dev, const char *name)
707 static inline void mei_dbgfs_deregister(struct mei_device *dev) {}
708 #endif /* CONFIG_DEBUG_FS */
710 int mei_register(struct mei_device *dev, struct device *parent);
711 void mei_deregister(struct mei_device *dev);
713 #define MEI_HDR_FMT "hdr:host=%02d me=%02d len=%d internal=%1d comp=%1d"
714 #define MEI_HDR_PRM(hdr) \
715 (hdr)->host_addr, (hdr)->me_addr, \
716 (hdr)->length, (hdr)->internal, (hdr)->msg_complete
718 ssize_t mei_fw_status2str(struct mei_fw_status *fw_sts, char *buf, size_t len);
720 * mei_fw_status_str - fetch and convert fw status registers to printable string
722 * @dev: the device structure
723 * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
724 * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
726 * Return: number of bytes written or < 0 on failure
728 static inline ssize_t mei_fw_status_str(struct mei_device *dev,
729 char *buf, size_t len)
731 struct mei_fw_status fw_status;
736 ret = mei_fw_status(dev, &fw_status);
740 ret = mei_fw_status2str(&fw_status, buf, MEI_FW_STATUS_STR_SZ);