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
18 #include <linux/export.h>
19 #include <linux/kthread.h>
20 #include <linux/interrupt.h>
22 #include <linux/jiffies.h>
23 #include <linux/slab.h>
25 #include <linux/mei.h>
33 * mei_irq_compl_handler - dispatch complete handlers
34 * for the completed callbacks
37 * @compl_list: list of completed cbs
39 void mei_irq_compl_handler(struct mei_device *dev, struct mei_cl_cb *compl_list)
41 struct mei_cl_cb *cb, *next;
44 list_for_each_entry_safe(cb, next, &compl_list->list, list) {
50 dev_dbg(dev->dev, "completing call back.\n");
51 if (cl == &dev->iamthif_cl)
52 mei_amthif_complete(dev, cb);
54 mei_cl_complete(cl, cb);
57 EXPORT_SYMBOL_GPL(mei_irq_compl_handler);
60 * mei_cl_hbm_equal - check if hbm is addressed to the client
63 * @mei_hdr: header of mei client message
65 * Return: true if matches, false otherwise
67 static inline int mei_cl_hbm_equal(struct mei_cl *cl,
68 struct mei_msg_hdr *mei_hdr)
70 return cl->host_client_id == mei_hdr->host_addr &&
71 cl->me_client_id == mei_hdr->me_addr;
74 * mei_cl_is_reading - checks if the client
75 * is the one to read this message
78 * @mei_hdr: header of mei message
80 * Return: true on match and false otherwise
82 static bool mei_cl_is_reading(struct mei_cl *cl, struct mei_msg_hdr *mei_hdr)
84 return mei_cl_hbm_equal(cl, mei_hdr) &&
85 cl->state == MEI_FILE_CONNECTED &&
86 cl->reading_state != MEI_READ_COMPLETE;
90 * mei_cl_irq_read_msg - process client message
92 * @dev: the device structure
93 * @mei_hdr: header of mei client message
94 * @complete_list: An instance of our list structure
96 * Return: 0 on success, <0 on failure.
98 static int mei_cl_irq_read_msg(struct mei_device *dev,
99 struct mei_msg_hdr *mei_hdr,
100 struct mei_cl_cb *complete_list)
103 struct mei_cl_cb *cb, *next;
104 unsigned char *buffer = NULL;
106 list_for_each_entry_safe(cb, next, &dev->read_list.list, list) {
108 if (!cl || !mei_cl_is_reading(cl, mei_hdr))
111 cl->reading_state = MEI_READING;
113 if (cb->response_buffer.size == 0 ||
114 cb->response_buffer.data == NULL) {
115 cl_err(dev, cl, "response buffer is not allocated.\n");
120 if (cb->response_buffer.size < mei_hdr->length + cb->buf_idx) {
121 cl_dbg(dev, cl, "message overflow. size %d len %d idx %ld\n",
122 cb->response_buffer.size,
123 mei_hdr->length, cb->buf_idx);
124 buffer = krealloc(cb->response_buffer.data,
125 mei_hdr->length + cb->buf_idx,
132 cb->response_buffer.data = buffer;
133 cb->response_buffer.size =
134 mei_hdr->length + cb->buf_idx;
137 buffer = cb->response_buffer.data + cb->buf_idx;
138 mei_read_slots(dev, buffer, mei_hdr->length);
140 cb->buf_idx += mei_hdr->length;
141 if (mei_hdr->msg_complete) {
144 cl_dbg(dev, cl, "completed read length = %lu\n",
146 list_add_tail(&cb->list, &complete_list->list);
151 dev_dbg(dev->dev, "message read\n");
153 mei_read_slots(dev, dev->rd_msg_buf, mei_hdr->length);
154 dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n",
155 MEI_HDR_PRM(mei_hdr));
162 * mei_cl_irq_disconnect_rsp - send disconnection response message
165 * @cb: callback block.
166 * @cmpl_list: complete list.
168 * Return: 0, OK; otherwise, error.
170 static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
171 struct mei_cl_cb *cmpl_list)
173 struct mei_device *dev = cl->dev;
178 slots = mei_hbuf_empty_slots(dev);
179 msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_response));
181 if (slots < msg_slots)
184 ret = mei_hbm_cl_disconnect_rsp(dev, cl);
186 cl->state = MEI_FILE_DISCONNECTED;
197 * mei_cl_irq_disconnect - processes close related operation from
198 * interrupt thread context - send disconnect request
201 * @cb: callback block.
202 * @cmpl_list: complete list.
204 * Return: 0, OK; otherwise, error.
206 static int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
207 struct mei_cl_cb *cmpl_list)
209 struct mei_device *dev = cl->dev;
213 msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
214 slots = mei_hbuf_empty_slots(dev);
216 if (slots < msg_slots)
219 if (mei_hbm_cl_disconnect_req(dev, cl)) {
222 list_move_tail(&cb->list, &cmpl_list->list);
226 cl->state = MEI_FILE_DISCONNECTING;
229 list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
230 cl->timer_count = MEI_CONNECT_TIMEOUT;
237 * mei_cl_irq_read - processes client read related operation from the
238 * interrupt thread context - request for flow control credits
241 * @cb: callback block.
242 * @cmpl_list: complete list.
244 * Return: 0, OK; otherwise, error.
246 static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
247 struct mei_cl_cb *cmpl_list)
249 struct mei_device *dev = cl->dev;
254 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
255 slots = mei_hbuf_empty_slots(dev);
257 if (slots < msg_slots)
260 ret = mei_hbm_cl_flow_control_req(dev, cl);
264 list_move_tail(&cb->list, &cmpl_list->list);
268 list_move_tail(&cb->list, &dev->read_list.list);
275 * mei_cl_irq_connect - send connect request in irq_thread context
278 * @cb: callback block.
279 * @cmpl_list: complete list.
281 * Return: 0, OK; otherwise, error.
283 static int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
284 struct mei_cl_cb *cmpl_list)
286 struct mei_device *dev = cl->dev;
291 msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
292 slots = mei_hbuf_empty_slots(dev);
294 if (mei_cl_is_other_connecting(cl))
297 if (slots < msg_slots)
300 cl->state = MEI_FILE_CONNECTING;
302 ret = mei_hbm_cl_connect_req(dev, cl);
310 list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
311 cl->timer_count = MEI_CONNECT_TIMEOUT;
317 * mei_irq_read_handler - bottom half read routine after ISR to
318 * handle the read processing.
320 * @dev: the device structure
321 * @cmpl_list: An instance of our list structure
322 * @slots: slots to read.
324 * Return: 0 on success, <0 on failure.
326 int mei_irq_read_handler(struct mei_device *dev,
327 struct mei_cl_cb *cmpl_list, s32 *slots)
329 struct mei_msg_hdr *mei_hdr;
333 if (!dev->rd_msg_hdr) {
334 dev->rd_msg_hdr = mei_read_hdr(dev);
336 dev_dbg(dev->dev, "slots =%08x.\n", *slots);
338 mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr;
339 dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
341 if (mei_hdr->reserved || !dev->rd_msg_hdr) {
342 dev_err(dev->dev, "corrupted message header 0x%08X\n",
348 if (mei_slots2data(*slots) < mei_hdr->length) {
349 dev_err(dev->dev, "less data available than length=%08x.\n",
351 /* we can't read the message */
357 if (mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0) {
358 ret = mei_hbm_dispatch(dev, mei_hdr);
360 dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n",
367 /* find recipient cl */
368 list_for_each_entry(cl, &dev->file_list, link) {
369 if (mei_cl_hbm_equal(cl, mei_hdr)) {
370 cl_dbg(dev, cl, "got a message\n");
375 /* if no recipient cl was found we assume corrupted header */
376 if (&cl->link == &dev->file_list) {
377 dev_err(dev->dev, "no destination client found 0x%08X\n",
383 if (mei_hdr->host_addr == dev->iamthif_cl.host_client_id &&
384 MEI_FILE_CONNECTED == dev->iamthif_cl.state &&
385 dev->iamthif_state == MEI_IAMTHIF_READING) {
387 ret = mei_amthif_irq_read_msg(dev, mei_hdr, cmpl_list);
389 dev_err(dev->dev, "mei_amthif_irq_read_msg failed = %d\n",
394 ret = mei_cl_irq_read_msg(dev, mei_hdr, cmpl_list);
396 dev_err(dev->dev, "mei_cl_irq_read_msg failed = %d\n",
403 /* reset the number of slots and header */
404 *slots = mei_count_full_read_slots(dev);
407 if (*slots == -EOVERFLOW) {
408 /* overflow - reset */
409 dev_err(dev->dev, "resetting due to slots overflow.\n");
410 /* set the event since message has been read */
417 EXPORT_SYMBOL_GPL(mei_irq_read_handler);
421 * mei_irq_write_handler - dispatch write requests
424 * @dev: the device structure
425 * @cmpl_list: An instance of our list structure
427 * Return: 0 on success, <0 on failure.
429 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
433 struct mei_cl_cb *cb, *next;
434 struct mei_cl_cb *list;
439 if (!mei_hbuf_acquire(dev))
442 slots = mei_hbuf_empty_slots(dev);
446 /* complete all waiting for write CB */
447 dev_dbg(dev->dev, "complete all waiting for write cb.\n");
449 list = &dev->write_waiting_list;
450 list_for_each_entry_safe(cb, next, &list->list, list) {
457 if (cb->fop_type == MEI_FOP_WRITE &&
458 cl != &dev->iamthif_cl) {
459 cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
460 cl->writing_state = MEI_WRITE_COMPLETE;
461 list_add_tail(&cb->list, &cmpl_list->list);
463 if (cl == &dev->iamthif_cl) {
464 cl_dbg(dev, cl, "check iamthif flow control.\n");
465 if (dev->iamthif_flow_control_pending) {
466 ret = mei_amthif_irq_read(dev, &slots);
473 if (dev->wd_state == MEI_WD_STOPPING) {
474 dev->wd_state = MEI_WD_IDLE;
475 wake_up(&dev->wait_stop_wd);
478 if (mei_cl_is_connected(&dev->wd_cl)) {
479 if (dev->wd_pending &&
480 mei_cl_flow_ctrl_creds(&dev->wd_cl) > 0) {
481 ret = mei_wd_send(dev);
484 dev->wd_pending = false;
488 /* complete control write list CB */
489 dev_dbg(dev->dev, "complete control write list cb.\n");
490 list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list.list, list) {
496 switch (cb->fop_type) {
497 case MEI_FOP_DISCONNECT:
498 /* send disconnect message */
499 ret = mei_cl_irq_disconnect(cl, cb, cmpl_list);
505 /* send flow control message */
506 ret = mei_cl_irq_read(cl, cb, cmpl_list);
511 case MEI_FOP_CONNECT:
512 /* connect message */
513 ret = mei_cl_irq_connect(cl, cb, cmpl_list);
518 case MEI_FOP_DISCONNECT_RSP:
519 /* send disconnect resp */
520 ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
529 /* complete write list CB */
530 dev_dbg(dev->dev, "complete write list cb.\n");
531 list_for_each_entry_safe(cb, next, &dev->write_list.list, list) {
535 if (cl == &dev->iamthif_cl)
536 ret = mei_amthif_irq_write(cl, cb, cmpl_list);
538 ret = mei_cl_irq_write(cl, cb, cmpl_list);
544 EXPORT_SYMBOL_GPL(mei_irq_write_handler);
549 * mei_timer - timer function.
551 * @work: pointer to the work_struct structure
554 void mei_timer(struct work_struct *work)
556 unsigned long timeout;
559 struct mei_device *dev = container_of(work,
560 struct mei_device, timer_work.work);
563 mutex_lock(&dev->device_lock);
565 /* Catch interrupt stalls during HBM init handshake */
566 if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
567 dev->hbm_state != MEI_HBM_IDLE) {
569 if (dev->init_clients_timer) {
570 if (--dev->init_clients_timer == 0) {
571 dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n",
579 if (dev->dev_state != MEI_DEV_ENABLED)
582 /*** connect/disconnect timeouts ***/
583 list_for_each_entry(cl, &dev->file_list, link) {
584 if (cl->timer_count) {
585 if (--cl->timer_count == 0) {
586 dev_err(dev->dev, "timer: connect/disconnect timeout.\n");
593 if (!mei_cl_is_connected(&dev->iamthif_cl))
596 if (dev->iamthif_stall_timer) {
597 if (--dev->iamthif_stall_timer == 0) {
598 dev_err(dev->dev, "timer: amthif hanged.\n");
600 dev->iamthif_msg_buf_size = 0;
601 dev->iamthif_msg_buf_index = 0;
602 dev->iamthif_canceled = false;
603 dev->iamthif_ioctl = true;
604 dev->iamthif_state = MEI_IAMTHIF_IDLE;
605 dev->iamthif_timer = 0;
607 mei_io_cb_free(dev->iamthif_current_cb);
608 dev->iamthif_current_cb = NULL;
610 dev->iamthif_file_object = NULL;
611 mei_amthif_run_next_cmd(dev);
615 if (dev->iamthif_timer) {
617 timeout = dev->iamthif_timer +
618 mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
620 dev_dbg(dev->dev, "dev->iamthif_timer = %ld\n",
622 dev_dbg(dev->dev, "timeout = %ld\n", timeout);
623 dev_dbg(dev->dev, "jiffies = %ld\n", jiffies);
624 if (time_after(jiffies, timeout)) {
626 * User didn't read the AMTHI data on time (15sec)
627 * freeing AMTHI for other requests
630 dev_dbg(dev->dev, "freeing AMTHI for other requests\n");
632 mei_io_list_flush(&dev->amthif_rd_complete_list,
634 mei_io_cb_free(dev->iamthif_current_cb);
635 dev->iamthif_current_cb = NULL;
637 dev->iamthif_file_object->private_data = NULL;
638 dev->iamthif_file_object = NULL;
639 dev->iamthif_timer = 0;
640 mei_amthif_run_next_cmd(dev);
645 if (dev->dev_state != MEI_DEV_DISABLED)
646 schedule_delayed_work(&dev->timer_work, 2 * HZ);
647 mutex_unlock(&dev->device_lock);