1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright (c) 2003-2019, Intel Corporation. All rights reserved.
4 * Intel Management Engine Interface (Intel MEI) Linux driver
10 #include <linux/types.h>
11 #include <linux/cdev.h>
12 #include <linux/poll.h>
13 #include <linux/mei.h>
14 #include <linux/mei_cl_bus.h>
19 #define MEI_SLOT_SIZE sizeof(u32)
20 #define MEI_RD_MSG_BUF_SIZE (128 * MEI_SLOT_SIZE)
23 * Number of Maximum MEI Clients
25 #define MEI_CLIENTS_MAX 256
28 * maximum number of consecutive resets
30 #define MEI_MAX_CONSEC_RESET 3
33 * Number of File descriptors/handles
34 * that can be opened to the driver.
36 * Limit to 255: 256 Total Clients
37 * minus internal client for MEI Bus Messages
39 #define MEI_MAX_OPEN_HANDLE_COUNT (MEI_CLIENTS_MAX - 1)
43 MEI_FILE_UNINITIALIZED = 0,
44 MEI_FILE_INITIALIZING,
47 MEI_FILE_DISCONNECTING,
48 MEI_FILE_DISCONNECT_REPLY,
49 MEI_FILE_DISCONNECT_REQUIRED,
50 MEI_FILE_DISCONNECTED,
53 /* MEI device states */
55 MEI_DEV_INITIALIZING = 0,
64 const char *mei_dev_state_str(int state);
66 enum mei_file_transaction_states {
73 * enum mei_cb_file_ops - file operation associated with the callback
75 * @MEI_FOP_WRITE: write
76 * @MEI_FOP_CONNECT: connect
77 * @MEI_FOP_DISCONNECT: disconnect
78 * @MEI_FOP_DISCONNECT_RSP: disconnect response
79 * @MEI_FOP_NOTIFY_START: start notification
80 * @MEI_FOP_NOTIFY_STOP: stop notification
82 enum mei_cb_file_ops {
87 MEI_FOP_DISCONNECT_RSP,
93 * enum mei_cl_io_mode - io mode between driver and fw
95 * @MEI_CL_IO_TX_BLOCKING: send is blocking
96 * @MEI_CL_IO_TX_INTERNAL: internal communication between driver and FW
98 * @MEI_CL_IO_RX_NONBLOCK: recv is non-blocking
100 enum mei_cl_io_mode {
101 MEI_CL_IO_TX_BLOCKING = BIT(0),
102 MEI_CL_IO_TX_INTERNAL = BIT(1),
104 MEI_CL_IO_RX_NONBLOCK = BIT(2),
108 * Intel MEI message data struct
110 struct mei_msg_data {
116 * struct mei_dma_dscr - dma address descriptor
118 * @vaddr: dma buffer virtual address
119 * @daddr: dma buffer physical address
120 * @size : dma buffer size
122 struct mei_dma_dscr {
128 /* Maximum number of processed FW status registers */
129 #define MEI_FW_STATUS_MAX 6
130 /* Minimal buffer for FW status string (8 bytes in dw + space or '\0') */
131 #define MEI_FW_STATUS_STR_SZ (MEI_FW_STATUS_MAX * (8 + 1))
135 * struct mei_fw_status - storage of FW status data
137 * @count: number of actually available elements in array
138 * @status: FW status registers
140 struct mei_fw_status {
142 u32 status[MEI_FW_STATUS_MAX];
146 * struct mei_me_client - representation of me (fw) client
148 * @list: link in me client list
149 * @refcnt: struct reference count
150 * @props: client properties
151 * @client_id: me client id
152 * @tx_flow_ctrl_creds: flow control credits
153 * @connect_count: number connections to this client
154 * @bus_added: added to bus
156 struct mei_me_client {
157 struct list_head list;
159 struct mei_client_properties props;
161 u8 tx_flow_ctrl_creds;
170 * struct mei_cl_cb - file operation callback structure
172 * @list: link in callback queue
173 * @cl: file client who is running this operation
174 * @fop_type: file operation type
175 * @buf: buffer for data associated with the callback
176 * @buf_idx: last read index
178 * @fp: pointer to file structure
179 * @status: io status of the cb
180 * @internal: communication between driver and FW flag
181 * @blocking: transmission blocking mode
184 struct list_head list;
186 enum mei_cb_file_ops fop_type;
187 struct mei_msg_data buf;
190 const struct file *fp;
197 * struct mei_cl_vtag - file pointer to vtag mapping structure
199 * @list: link in map queue
201 * @vtag: corresponding vtag
202 * @pending_read: the read is pending on this file
205 struct list_head list;
206 const struct file *fp;
212 * struct mei_cl - me client host representation
213 * carried in file->private_data
215 * @link: link in the clients list
216 * @dev: mei parent device
217 * @state: file operation state
218 * @tx_wait: wait queue for tx completion
219 * @rx_wait: wait queue for rx completion
220 * @wait: wait queue for management operation
221 * @ev_wait: notification wait queue
222 * @ev_async: event async notification
223 * @status: connection status
224 * @me_cl: fw client connected
225 * @fp: file associated with client
226 * @host_client_id: host id
227 * @vtag_map: vtag map
228 * @tx_flow_ctrl_creds: transmit flow credentials
229 * @rx_flow_ctrl_creds: receive flow credentials
230 * @timer_count: watchdog timer for operation completion
231 * @notify_en: notification - enabled/disabled
232 * @notify_ev: pending notification event
233 * @tx_cb_queued: number of tx callbacks in queue
234 * @writing_state: state of the tx
235 * @rd_pending: pending read credits
236 * @rd_completed_lock: protects rd_completed queue
237 * @rd_completed: completed read
239 * @cldev: device on the mei client bus
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;
248 wait_queue_head_t ev_wait;
249 struct fasync_struct *ev_async;
251 struct mei_me_client *me_cl;
252 const struct file *fp;
254 struct list_head vtag_map;
255 u8 tx_flow_ctrl_creds;
256 u8 rx_flow_ctrl_creds;
261 enum mei_file_transaction_states writing_state;
262 struct list_head rd_pending;
263 spinlock_t rd_completed_lock; /* protects rd_completed queue */
264 struct list_head rd_completed;
266 struct mei_cl_device *cldev;
269 #define MEI_TX_QUEUE_LIMIT_DEFAULT 50
270 #define MEI_TX_QUEUE_LIMIT_MAX 255
271 #define MEI_TX_QUEUE_LIMIT_MIN 30
274 * struct mei_hw_ops - hw specific ops
276 * @host_is_ready : query for host readiness
278 * @hw_is_ready : query if hw is ready
279 * @hw_reset : reset hw
280 * @hw_start : start hw after reset
281 * @hw_config : configure hw
283 * @fw_status : get fw status registers
284 * @trc_status : get trc status register
285 * @pg_state : power gating state of the device
286 * @pg_in_transition : is device now in pg transition
287 * @pg_is_enabled : is power gating enabled
289 * @intr_clear : clear pending interrupts
290 * @intr_enable : enable interrupts
291 * @intr_disable : disable interrupts
292 * @synchronize_irq : synchronize irqs
294 * @hbuf_free_slots : query for write buffer empty slots
295 * @hbuf_is_ready : query if write buffer is empty
296 * @hbuf_depth : query for write buffer depth
298 * @write : write a message to FW
300 * @rdbuf_full_slots : query how many slots are filled
302 * @read_hdr : get first 4 bytes (header)
303 * @read : read a buffer from the FW
307 bool (*host_is_ready)(struct mei_device *dev);
309 bool (*hw_is_ready)(struct mei_device *dev);
310 int (*hw_reset)(struct mei_device *dev, bool enable);
311 int (*hw_start)(struct mei_device *dev);
312 int (*hw_config)(struct mei_device *dev);
314 int (*fw_status)(struct mei_device *dev, struct mei_fw_status *fw_sts);
315 int (*trc_status)(struct mei_device *dev, u32 *trc);
317 enum mei_pg_state (*pg_state)(struct mei_device *dev);
318 bool (*pg_in_transition)(struct mei_device *dev);
319 bool (*pg_is_enabled)(struct mei_device *dev);
321 void (*intr_clear)(struct mei_device *dev);
322 void (*intr_enable)(struct mei_device *dev);
323 void (*intr_disable)(struct mei_device *dev);
324 void (*synchronize_irq)(struct mei_device *dev);
326 int (*hbuf_free_slots)(struct mei_device *dev);
327 bool (*hbuf_is_ready)(struct mei_device *dev);
328 u32 (*hbuf_depth)(const struct mei_device *dev);
329 int (*write)(struct mei_device *dev,
330 const void *hdr, size_t hdr_len,
331 const void *data, size_t data_len);
333 int (*rdbuf_full_slots)(struct mei_device *dev);
335 u32 (*read_hdr)(const struct mei_device *dev);
336 int (*read)(struct mei_device *dev,
337 unsigned char *buf, unsigned long len);
341 void mei_cl_bus_rescan_work(struct work_struct *work);
342 void mei_cl_bus_dev_fixup(struct mei_cl_device *dev);
343 ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length, u8 vtag,
345 ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length, u8 *vtag,
346 unsigned int mode, unsigned long timeout);
347 bool mei_cl_bus_rx_event(struct mei_cl *cl);
348 bool mei_cl_bus_notify_event(struct mei_cl *cl);
349 void mei_cl_bus_remove_devices(struct mei_device *bus);
350 int mei_cl_bus_init(void);
351 void mei_cl_bus_exit(void);
354 * enum mei_pg_event - power gating transition events
356 * @MEI_PG_EVENT_IDLE: the driver is not in power gating transition
357 * @MEI_PG_EVENT_WAIT: the driver is waiting for a pg event to complete
358 * @MEI_PG_EVENT_RECEIVED: the driver received pg event
359 * @MEI_PG_EVENT_INTR_WAIT: the driver is waiting for a pg event interrupt
360 * @MEI_PG_EVENT_INTR_RECEIVED: the driver received pg event interrupt
365 MEI_PG_EVENT_RECEIVED,
366 MEI_PG_EVENT_INTR_WAIT,
367 MEI_PG_EVENT_INTR_RECEIVED,
371 * enum mei_pg_state - device internal power gating state
373 * @MEI_PG_OFF: device is not power gated - it is active
374 * @MEI_PG_ON: device is power gated - it is in lower power state
381 const char *mei_pg_state_str(enum mei_pg_state state);
384 * struct mei_fw_version - MEI FW version struct
386 * @platform: platform identifier
387 * @major: major version field
388 * @minor: minor version field
389 * @buildno: build number version field
390 * @hotfix: hotfix number version field
392 struct mei_fw_version {
400 #define MEI_MAX_FW_VER_BLOCKS 3
403 * struct mei_device - MEI private device struct
405 * @dev : device on a bus
406 * @cdev : character device
407 * @minor : minor number allocated for device
409 * @write_list : write pending list
410 * @write_waiting_list : write completion list
411 * @ctrl_wr_list : pending control write list
412 * @ctrl_rd_list : pending control read list
413 * @tx_queue_limit: tx queues per client linit
415 * @file_list : list of opened handles
416 * @open_handle_count: number of opened handles
418 * @device_lock : big device lock
419 * @timer_work : MEI timer delayed work (timeouts)
421 * @recvd_hw_ready : hw ready message received flag
423 * @wait_hw_ready : wait queue for receive HW ready message form FW
424 * @wait_pg : wait queue for receive PG message from FW
425 * @wait_hbm_start : wait queue for receive HBM start message from FW
427 * @reset_count : number of consecutive resets
428 * @dev_state : device state
429 * @hbm_state : state of host bus message protocol
430 * @init_clients_timer : HBM init handshake timeout
432 * @pg_event : power gating event
433 * @pg_domain : runtime PM domain
435 * @rd_msg_buf : control messages buffer
436 * @rd_msg_hdr : read message header storage
437 * @rd_msg_hdr_count : how many dwords were already read from header
439 * @hbuf_is_ready : query if the host host/write buffer is ready
440 * @dr_dscr: DMA ring descriptors: TX, RX, and CTRL
442 * @version : HBM protocol version in use
443 * @hbm_f_pg_supported : hbm feature pgi protocol
444 * @hbm_f_dc_supported : hbm feature dynamic clients
445 * @hbm_f_dot_supported : hbm feature disconnect on timeout
446 * @hbm_f_ev_supported : hbm feature event notification
447 * @hbm_f_fa_supported : hbm feature fixed address client
448 * @hbm_f_ie_supported : hbm feature immediate reply to enum request
449 * @hbm_f_os_supported : hbm feature support OS ver message
450 * @hbm_f_dr_supported : hbm feature dma ring supported
451 * @hbm_f_vt_supported : hbm feature vtag supported
452 * @hbm_f_cap_supported : hbm feature capabilities message supported
454 * @fw_ver : FW versions
456 * @fw_f_fw_ver_supported : fw feature: fw version supported
458 * @me_clients_rwsem: rw lock over me_clients list
459 * @me_clients : list of FW clients
460 * @me_clients_map : FW clients bit map
461 * @host_clients_map : host clients id pool
463 * @allow_fixed_address: allow user space to connect a fixed client
464 * @override_fixed_address: force allow fixed address behavior
466 * @reset_work : work item for the device reset
467 * @bus_rescan_work : work item for the bus rescan
469 * @device_list : mei client bus list
470 * @cl_bus_lock : client bus list lock
472 * @kind : kind of mei device
474 * @dbgfs_dir : debugfs mei root directory
476 * @ops: : hw specific operations
477 * @hw : hw specific data
484 struct list_head write_list;
485 struct list_head write_waiting_list;
486 struct list_head ctrl_wr_list;
487 struct list_head ctrl_rd_list;
490 struct list_head file_list;
491 long open_handle_count;
493 struct mutex device_lock;
494 struct delayed_work timer_work;
498 * waiting queue for receive message from FW
500 wait_queue_head_t wait_hw_ready;
501 wait_queue_head_t wait_pg;
502 wait_queue_head_t wait_hbm_start;
507 unsigned long reset_count;
508 enum mei_dev_state dev_state;
509 enum mei_hbm_state hbm_state;
510 u16 init_clients_timer;
513 * Power Gating support
515 enum mei_pg_event pg_event;
517 struct dev_pm_domain pg_domain;
518 #endif /* CONFIG_PM */
520 unsigned char rd_msg_buf[MEI_RD_MSG_BUF_SIZE];
521 u32 rd_msg_hdr[MEI_RD_MSG_BUF_SIZE];
522 int rd_msg_hdr_count;
527 struct mei_dma_dscr dr_dscr[DMA_DSCR_NUM];
529 struct hbm_version version;
530 unsigned int hbm_f_pg_supported:1;
531 unsigned int hbm_f_dc_supported:1;
532 unsigned int hbm_f_dot_supported:1;
533 unsigned int hbm_f_ev_supported:1;
534 unsigned int hbm_f_fa_supported:1;
535 unsigned int hbm_f_ie_supported:1;
536 unsigned int hbm_f_os_supported:1;
537 unsigned int hbm_f_dr_supported:1;
538 unsigned int hbm_f_vt_supported:1;
539 unsigned int hbm_f_cap_supported:1;
541 struct mei_fw_version fw_ver[MEI_MAX_FW_VER_BLOCKS];
543 unsigned int fw_f_fw_ver_supported:1;
545 struct rw_semaphore me_clients_rwsem;
546 struct list_head me_clients;
547 DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX);
548 DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
550 bool allow_fixed_address;
551 bool override_fixed_address;
553 struct work_struct reset_work;
554 struct work_struct bus_rescan_work;
556 /* List of bus devices */
557 struct list_head device_list;
558 struct mutex cl_bus_lock;
562 #if IS_ENABLED(CONFIG_DEBUG_FS)
563 struct dentry *dbgfs_dir;
564 #endif /* CONFIG_DEBUG_FS */
566 const struct mei_hw_ops *ops;
567 char hw[] __aligned(sizeof(void *));
570 static inline unsigned long mei_secs_to_jiffies(unsigned long sec)
572 return msecs_to_jiffies(sec * MSEC_PER_SEC);
576 * mei_data2slots - get slots number from a message length
578 * @length: size of the messages in bytes
580 * Return: number of slots
582 static inline u32 mei_data2slots(size_t length)
584 return DIV_ROUND_UP(length, MEI_SLOT_SIZE);
588 * mei_hbm2slots - get slots number from a hbm message length
589 * length + size of the mei message header
591 * @length: size of the messages in bytes
593 * Return: number of slots
595 static inline u32 mei_hbm2slots(size_t length)
597 return DIV_ROUND_UP(sizeof(struct mei_msg_hdr) + length, MEI_SLOT_SIZE);
601 * mei_slots2data - get data in slots - bytes from slots
603 * @slots: number of available slots
605 * Return: number of bytes in slots
607 static inline u32 mei_slots2data(int slots)
609 return slots * MEI_SLOT_SIZE;
613 * mei init function prototypes
615 void mei_device_init(struct mei_device *dev,
616 struct device *device,
617 const struct mei_hw_ops *hw_ops);
618 int mei_reset(struct mei_device *dev);
619 int mei_start(struct mei_device *dev);
620 int mei_restart(struct mei_device *dev);
621 void mei_stop(struct mei_device *dev);
622 void mei_cancel_work(struct mei_device *dev);
624 void mei_set_devstate(struct mei_device *dev, enum mei_dev_state state);
626 int mei_dmam_ring_alloc(struct mei_device *dev);
627 void mei_dmam_ring_free(struct mei_device *dev);
628 bool mei_dma_ring_is_allocated(struct mei_device *dev);
629 void mei_dma_ring_reset(struct mei_device *dev);
630 void mei_dma_ring_read(struct mei_device *dev, unsigned char *buf, u32 len);
631 void mei_dma_ring_write(struct mei_device *dev, unsigned char *buf, u32 len);
632 u32 mei_dma_ring_empty_slots(struct mei_device *dev);
635 * MEI interrupt functions prototype
638 void mei_timer(struct work_struct *work);
639 void mei_schedule_stall_timer(struct mei_device *dev);
640 int mei_irq_read_handler(struct mei_device *dev,
641 struct list_head *cmpl_list, s32 *slots);
643 int mei_irq_write_handler(struct mei_device *dev, struct list_head *cmpl_list);
644 void mei_irq_compl_handler(struct mei_device *dev, struct list_head *cmpl_list);
647 * Register Access Function
651 static inline int mei_hw_config(struct mei_device *dev)
653 return dev->ops->hw_config(dev);
656 static inline enum mei_pg_state mei_pg_state(struct mei_device *dev)
658 return dev->ops->pg_state(dev);
661 static inline bool mei_pg_in_transition(struct mei_device *dev)
663 return dev->ops->pg_in_transition(dev);
666 static inline bool mei_pg_is_enabled(struct mei_device *dev)
668 return dev->ops->pg_is_enabled(dev);
671 static inline int mei_hw_reset(struct mei_device *dev, bool enable)
673 return dev->ops->hw_reset(dev, enable);
676 static inline int mei_hw_start(struct mei_device *dev)
678 return dev->ops->hw_start(dev);
681 static inline void mei_clear_interrupts(struct mei_device *dev)
683 dev->ops->intr_clear(dev);
686 static inline void mei_enable_interrupts(struct mei_device *dev)
688 dev->ops->intr_enable(dev);
691 static inline void mei_disable_interrupts(struct mei_device *dev)
693 dev->ops->intr_disable(dev);
696 static inline void mei_synchronize_irq(struct mei_device *dev)
698 dev->ops->synchronize_irq(dev);
701 static inline bool mei_host_is_ready(struct mei_device *dev)
703 return dev->ops->host_is_ready(dev);
705 static inline bool mei_hw_is_ready(struct mei_device *dev)
707 return dev->ops->hw_is_ready(dev);
710 static inline bool mei_hbuf_is_ready(struct mei_device *dev)
712 return dev->ops->hbuf_is_ready(dev);
715 static inline int mei_hbuf_empty_slots(struct mei_device *dev)
717 return dev->ops->hbuf_free_slots(dev);
720 static inline u32 mei_hbuf_depth(const struct mei_device *dev)
722 return dev->ops->hbuf_depth(dev);
725 static inline int mei_write_message(struct mei_device *dev,
726 const void *hdr, size_t hdr_len,
727 const void *data, size_t data_len)
729 return dev->ops->write(dev, hdr, hdr_len, data, data_len);
732 static inline u32 mei_read_hdr(const struct mei_device *dev)
734 return dev->ops->read_hdr(dev);
737 static inline void mei_read_slots(struct mei_device *dev,
738 unsigned char *buf, unsigned long len)
740 dev->ops->read(dev, buf, len);
743 static inline int mei_count_full_read_slots(struct mei_device *dev)
745 return dev->ops->rdbuf_full_slots(dev);
748 static inline int mei_trc_status(struct mei_device *dev, u32 *trc)
750 if (dev->ops->trc_status)
751 return dev->ops->trc_status(dev, trc);
755 static inline int mei_fw_status(struct mei_device *dev,
756 struct mei_fw_status *fw_status)
758 return dev->ops->fw_status(dev, fw_status);
761 bool mei_hbuf_acquire(struct mei_device *dev);
763 bool mei_write_is_idle(struct mei_device *dev);
765 #if IS_ENABLED(CONFIG_DEBUG_FS)
766 void mei_dbgfs_register(struct mei_device *dev, const char *name);
767 void mei_dbgfs_deregister(struct mei_device *dev);
769 static inline void mei_dbgfs_register(struct mei_device *dev, const char *name) {}
770 static inline void mei_dbgfs_deregister(struct mei_device *dev) {}
771 #endif /* CONFIG_DEBUG_FS */
773 int mei_register(struct mei_device *dev, struct device *parent);
774 void mei_deregister(struct mei_device *dev);
776 #define MEI_HDR_FMT "hdr:host=%02d me=%02d len=%d dma=%1d ext=%1d internal=%1d comp=%1d"
777 #define MEI_HDR_PRM(hdr) \
778 (hdr)->host_addr, (hdr)->me_addr, \
779 (hdr)->length, (hdr)->dma_ring, (hdr)->extended, \
780 (hdr)->internal, (hdr)->msg_complete
782 ssize_t mei_fw_status2str(struct mei_fw_status *fw_sts, char *buf, size_t len);
784 * mei_fw_status_str - fetch and convert fw status registers to printable string
786 * @dev: the device structure
787 * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
788 * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
790 * Return: number of bytes written or < 0 on failure
792 static inline ssize_t mei_fw_status_str(struct mei_device *dev,
793 char *buf, size_t len)
795 struct mei_fw_status fw_status;
800 ret = mei_fw_status(dev, &fw_status);
804 ret = mei_fw_status2str(&fw_status, buf, MEI_FW_STATUS_STR_SZ);