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
17 #include <linux/kernel.h>
19 #include <linux/errno.h>
20 #include <linux/types.h>
21 #include <linux/fcntl.h>
22 #include <linux/aio.h>
23 #include <linux/pci.h>
24 #include <linux/ioctl.h>
25 #include <linux/cdev.h>
26 #include <linux/list.h>
27 #include <linux/delay.h>
28 #include <linux/sched.h>
29 #include <linux/uuid.h>
30 #include <linux/jiffies.h>
31 #include <linux/uaccess.h>
33 #include <linux/mei.h>
40 const uuid_le mei_amthif_guid = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d,
41 0xac, 0xa8, 0x46, 0xe0,
42 0xff, 0x65, 0x81, 0x4c);
45 * mei_amthif_reset_params - initializes mei device iamthif
47 * @dev: the device structure
49 void mei_amthif_reset_params(struct mei_device *dev)
51 /* reset iamthif parameters. */
52 dev->iamthif_current_cb = NULL;
53 dev->iamthif_msg_buf_size = 0;
54 dev->iamthif_msg_buf_index = 0;
55 dev->iamthif_canceled = false;
56 dev->iamthif_ioctl = false;
57 dev->iamthif_state = MEI_IAMTHIF_IDLE;
58 dev->iamthif_timer = 0;
59 dev->iamthif_stall_timer = 0;
60 dev->iamthif_open_count = 0;
64 * mei_amthif_host_init - mei initialization amthif client.
66 * @dev: the device structure
69 int mei_amthif_host_init(struct mei_device *dev)
71 struct mei_cl *cl = &dev->iamthif_cl;
72 unsigned char *msg_buf;
75 dev->iamthif_state = MEI_IAMTHIF_IDLE;
79 i = mei_me_cl_by_uuid(dev, &mei_amthif_guid);
82 dev_info(&dev->pdev->dev,
83 "amthif: failed to find the client %d\n", ret);
87 cl->me_client_id = dev->me_clients[i].client_id;
89 /* Assign iamthif_mtu to the value received from ME */
91 dev->iamthif_mtu = dev->me_clients[i].props.max_msg_length;
92 dev_dbg(&dev->pdev->dev, "IAMTHIF_MTU = %d\n",
93 dev->me_clients[i].props.max_msg_length);
95 kfree(dev->iamthif_msg_buf);
96 dev->iamthif_msg_buf = NULL;
98 /* allocate storage for ME message buffer */
99 msg_buf = kcalloc(dev->iamthif_mtu,
100 sizeof(unsigned char), GFP_KERNEL);
102 dev_err(&dev->pdev->dev, "amthif: memory allocation for ME message buffer failed.\n");
106 dev->iamthif_msg_buf = msg_buf;
108 ret = mei_cl_link(cl, MEI_IAMTHIF_HOST_CLIENT_ID);
111 dev_err(&dev->pdev->dev,
112 "amthif: failed link client %d\n", ret);
116 cl->state = MEI_FILE_CONNECTING;
118 ret = mei_cl_connect(cl, NULL);
120 dev->iamthif_state = MEI_IAMTHIF_IDLE;
126 * mei_amthif_find_read_list_entry - finds a amthilist entry for current file
128 * @dev: the device structure
129 * @file: pointer to file object
131 * returns returned a list entry on success, NULL on failure.
133 struct mei_cl_cb *mei_amthif_find_read_list_entry(struct mei_device *dev,
136 struct mei_cl_cb *cb;
138 list_for_each_entry(cb, &dev->amthif_rd_complete_list.list, list) {
139 if (cb->cl && cb->cl == &dev->iamthif_cl &&
140 cb->file_object == file)
148 * mei_amthif_read - read data from AMTHIF client
150 * @dev: the device structure
151 * @if_num: minor number
152 * @file: pointer to file object
153 * @*ubuf: pointer to user data in user space
154 * @length: data length to read
155 * @offset: data read offset
157 * Locking: called under "dev->device_lock" lock
160 * returned data length on success,
161 * zero if no data to read,
162 * negative on failure.
164 int mei_amthif_read(struct mei_device *dev, struct file *file,
165 char __user *ubuf, size_t length, loff_t *offset)
169 struct mei_cl_cb *cb = NULL;
170 struct mei_cl *cl = file->private_data;
171 unsigned long timeout;
174 /* Only possible if we are in timeout */
175 if (!cl || cl != &dev->iamthif_cl) {
176 dev_dbg(&dev->pdev->dev, "bad file ext.\n");
180 i = mei_me_cl_by_id(dev, dev->iamthif_cl.me_client_id);
183 dev_dbg(&dev->pdev->dev, "amthif client not found.\n");
186 dev_dbg(&dev->pdev->dev, "checking amthif data\n");
187 cb = mei_amthif_find_read_list_entry(dev, file);
189 /* Check for if we can block or not*/
190 if (cb == NULL && file->f_flags & O_NONBLOCK)
194 dev_dbg(&dev->pdev->dev, "waiting for amthif data\n");
196 /* unlock the Mutex */
197 mutex_unlock(&dev->device_lock);
199 wait_ret = wait_event_interruptible(dev->iamthif_cl.wait,
200 (cb = mei_amthif_find_read_list_entry(dev, file)));
202 /* Locking again the Mutex */
203 mutex_lock(&dev->device_lock);
208 dev_dbg(&dev->pdev->dev, "woke up from sleep\n");
212 dev_dbg(&dev->pdev->dev, "Got amthif data\n");
213 dev->iamthif_timer = 0;
216 timeout = cb->read_time +
217 mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
218 dev_dbg(&dev->pdev->dev, "amthif timeout = %lud\n",
221 if (time_after(jiffies, timeout)) {
222 dev_dbg(&dev->pdev->dev, "amthif Time out\n");
223 /* 15 sec for the message has expired */
229 /* if the whole message will fit remove it from the list */
230 if (cb->buf_idx >= *offset && length >= (cb->buf_idx - *offset))
232 else if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
233 /* end of the message has been reached */
238 /* else means that not full buffer will be read and do not
239 * remove message from deletion list
242 dev_dbg(&dev->pdev->dev, "amthif cb->response_buffer size - %d\n",
243 cb->response_buffer.size);
244 dev_dbg(&dev->pdev->dev, "amthif cb->buf_idx - %lu\n", cb->buf_idx);
246 /* length is being truncated to PAGE_SIZE, however,
247 * the buf_idx may point beyond */
248 length = min_t(size_t, length, (cb->buf_idx - *offset));
250 if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length))
254 if ((*offset + length) < cb->buf_idx) {
260 dev_dbg(&dev->pdev->dev, "free amthif cb memory.\n");
268 * mei_amthif_send_cmd - send amthif command to the ME
270 * @dev: the device structure
271 * @cb: mei call back struct
273 * returns 0 on success, <0 on failure.
276 static int mei_amthif_send_cmd(struct mei_device *dev, struct mei_cl_cb *cb)
278 struct mei_msg_hdr mei_hdr;
284 dev_dbg(&dev->pdev->dev, "write data to amthif client.\n");
286 dev->iamthif_state = MEI_IAMTHIF_WRITING;
287 dev->iamthif_current_cb = cb;
288 dev->iamthif_file_object = cb->file_object;
289 dev->iamthif_canceled = false;
290 dev->iamthif_ioctl = true;
291 dev->iamthif_msg_buf_size = cb->request_buffer.size;
292 memcpy(dev->iamthif_msg_buf, cb->request_buffer.data,
293 cb->request_buffer.size);
295 ret = mei_cl_flow_ctrl_creds(&dev->iamthif_cl);
299 if (ret && mei_hbuf_acquire(dev)) {
301 if (cb->request_buffer.size > mei_hbuf_max_len(dev)) {
302 mei_hdr.length = mei_hbuf_max_len(dev);
303 mei_hdr.msg_complete = 0;
305 mei_hdr.length = cb->request_buffer.size;
306 mei_hdr.msg_complete = 1;
309 mei_hdr.host_addr = dev->iamthif_cl.host_client_id;
310 mei_hdr.me_addr = dev->iamthif_cl.me_client_id;
311 mei_hdr.reserved = 0;
312 mei_hdr.internal = 0;
313 dev->iamthif_msg_buf_index += mei_hdr.length;
314 ret = mei_write_message(dev, &mei_hdr, dev->iamthif_msg_buf);
318 if (mei_hdr.msg_complete) {
319 if (mei_cl_flow_ctrl_reduce(&dev->iamthif_cl))
321 dev->iamthif_flow_control_pending = true;
322 dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
323 dev_dbg(&dev->pdev->dev, "add amthif cb to write waiting list\n");
324 dev->iamthif_current_cb = cb;
325 dev->iamthif_file_object = cb->file_object;
326 list_add_tail(&cb->list, &dev->write_waiting_list.list);
328 dev_dbg(&dev->pdev->dev, "message does not complete, so add amthif cb to write list.\n");
329 list_add_tail(&cb->list, &dev->write_list.list);
332 list_add_tail(&cb->list, &dev->write_list.list);
338 * mei_amthif_write - write amthif data to amthif client
340 * @dev: the device structure
341 * @cb: mei call back struct
343 * returns 0 on success, <0 on failure.
346 int mei_amthif_write(struct mei_device *dev, struct mei_cl_cb *cb)
353 ret = mei_io_cb_alloc_resp_buf(cb, dev->iamthif_mtu);
357 cb->fop_type = MEI_FOP_WRITE;
359 if (!list_empty(&dev->amthif_cmd_list.list) ||
360 dev->iamthif_state != MEI_IAMTHIF_IDLE) {
361 dev_dbg(&dev->pdev->dev,
362 "amthif state = %d\n", dev->iamthif_state);
363 dev_dbg(&dev->pdev->dev, "AMTHIF: add cb to the wait list\n");
364 list_add_tail(&cb->list, &dev->amthif_cmd_list.list);
367 return mei_amthif_send_cmd(dev, cb);
370 * mei_amthif_run_next_cmd
372 * @dev: the device structure
374 * returns 0 on success, <0 on failure.
376 void mei_amthif_run_next_cmd(struct mei_device *dev)
378 struct mei_cl_cb *pos = NULL;
379 struct mei_cl_cb *next = NULL;
385 dev->iamthif_msg_buf_size = 0;
386 dev->iamthif_msg_buf_index = 0;
387 dev->iamthif_canceled = false;
388 dev->iamthif_ioctl = true;
389 dev->iamthif_state = MEI_IAMTHIF_IDLE;
390 dev->iamthif_timer = 0;
391 dev->iamthif_file_object = NULL;
393 dev_dbg(&dev->pdev->dev, "complete amthif cmd_list cb.\n");
395 list_for_each_entry_safe(pos, next, &dev->amthif_cmd_list.list, list) {
396 list_del(&pos->list);
398 if (pos->cl && pos->cl == &dev->iamthif_cl) {
399 status = mei_amthif_send_cmd(dev, pos);
401 dev_dbg(&dev->pdev->dev,
402 "amthif write failed status = %d\n",
412 unsigned int mei_amthif_poll(struct mei_device *dev,
413 struct file *file, poll_table *wait)
415 unsigned int mask = 0;
417 poll_wait(file, &dev->iamthif_cl.wait, wait);
419 mutex_lock(&dev->device_lock);
420 if (!mei_cl_is_connected(&dev->iamthif_cl)) {
424 } else if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE &&
425 dev->iamthif_file_object == file) {
427 mask |= (POLLIN | POLLRDNORM);
428 dev_dbg(&dev->pdev->dev, "run next amthif cb\n");
429 mei_amthif_run_next_cmd(dev);
431 mutex_unlock(&dev->device_lock);
439 * mei_amthif_irq_write - write iamthif command in irq thread context.
441 * @dev: the device structure.
442 * @cb_pos: callback block.
443 * @cl: private data of the file object.
444 * @cmpl_list: complete list.
446 * returns 0, OK; otherwise, error.
448 int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
449 struct mei_cl_cb *cmpl_list)
451 struct mei_device *dev = cl->dev;
452 struct mei_msg_hdr mei_hdr;
453 size_t len = dev->iamthif_msg_buf_size - dev->iamthif_msg_buf_index;
454 u32 msg_slots = mei_data2slots(len);
458 rets = mei_cl_flow_ctrl_creds(cl);
463 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
467 mei_hdr.host_addr = cl->host_client_id;
468 mei_hdr.me_addr = cl->me_client_id;
469 mei_hdr.reserved = 0;
470 mei_hdr.internal = 0;
472 slots = mei_hbuf_empty_slots(dev);
474 if (slots >= msg_slots) {
475 mei_hdr.length = len;
476 mei_hdr.msg_complete = 1;
477 /* Split the message only if we can write the whole host buffer */
478 } else if (slots == dev->hbuf_depth) {
480 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
481 mei_hdr.length = len;
482 mei_hdr.msg_complete = 0;
484 /* wait for next time the host buffer is empty */
488 dev_dbg(&dev->pdev->dev, MEI_HDR_FMT, MEI_HDR_PRM(&mei_hdr));
490 rets = mei_write_message(dev, &mei_hdr,
491 dev->iamthif_msg_buf + dev->iamthif_msg_buf_index);
493 dev->iamthif_state = MEI_IAMTHIF_IDLE;
499 if (mei_cl_flow_ctrl_reduce(cl))
502 dev->iamthif_msg_buf_index += mei_hdr.length;
505 if (mei_hdr.msg_complete) {
506 dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
507 dev->iamthif_flow_control_pending = true;
509 /* save iamthif cb sent to amthif client */
510 cb->buf_idx = dev->iamthif_msg_buf_index;
511 dev->iamthif_current_cb = cb;
513 list_move_tail(&cb->list, &dev->write_waiting_list.list);
521 * mei_amthif_irq_read_message - read routine after ISR to
522 * handle the read amthif message
524 * @dev: the device structure
525 * @mei_hdr: header of amthif message
526 * @complete_list: An instance of our list structure
528 * returns 0 on success, <0 on failure.
530 int mei_amthif_irq_read_msg(struct mei_device *dev,
531 struct mei_msg_hdr *mei_hdr,
532 struct mei_cl_cb *complete_list)
534 struct mei_cl_cb *cb;
535 unsigned char *buffer;
537 BUG_ON(mei_hdr->me_addr != dev->iamthif_cl.me_client_id);
538 BUG_ON(dev->iamthif_state != MEI_IAMTHIF_READING);
540 buffer = dev->iamthif_msg_buf + dev->iamthif_msg_buf_index;
541 BUG_ON(dev->iamthif_mtu < dev->iamthif_msg_buf_index + mei_hdr->length);
543 mei_read_slots(dev, buffer, mei_hdr->length);
545 dev->iamthif_msg_buf_index += mei_hdr->length;
547 if (!mei_hdr->msg_complete)
550 dev_dbg(&dev->pdev->dev, "amthif_message_buffer_index =%d\n",
553 dev_dbg(&dev->pdev->dev, "completed amthif read.\n ");
554 if (!dev->iamthif_current_cb)
557 cb = dev->iamthif_current_cb;
558 dev->iamthif_current_cb = NULL;
563 dev->iamthif_stall_timer = 0;
564 cb->buf_idx = dev->iamthif_msg_buf_index;
565 cb->read_time = jiffies;
566 if (dev->iamthif_ioctl && cb->cl == &dev->iamthif_cl) {
567 /* found the iamthif cb */
568 dev_dbg(&dev->pdev->dev, "complete the amthif read cb.\n ");
569 dev_dbg(&dev->pdev->dev, "add the amthif read cb to complete.\n ");
570 list_add_tail(&cb->list, &complete_list->list);
576 * mei_amthif_irq_read - prepares to read amthif data.
578 * @dev: the device structure.
579 * @slots: free slots.
581 * returns 0, OK; otherwise, error.
583 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots)
585 u32 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
587 if (*slots < msg_slots)
592 if (mei_hbm_cl_flow_control_req(dev, &dev->iamthif_cl)) {
593 dev_dbg(&dev->pdev->dev, "iamthif flow control failed\n");
597 dev_dbg(&dev->pdev->dev, "iamthif flow control success\n");
598 dev->iamthif_state = MEI_IAMTHIF_READING;
599 dev->iamthif_flow_control_pending = false;
600 dev->iamthif_msg_buf_index = 0;
601 dev->iamthif_msg_buf_size = 0;
602 dev->iamthif_stall_timer = MEI_IAMTHIF_STALL_TIMER;
603 dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
608 * mei_amthif_complete - complete amthif callback.
610 * @dev: the device structure.
611 * @cb_pos: callback block.
613 void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb)
615 if (dev->iamthif_canceled != 1) {
616 dev->iamthif_state = MEI_IAMTHIF_READ_COMPLETE;
617 dev->iamthif_stall_timer = 0;
618 memcpy(cb->response_buffer.data,
619 dev->iamthif_msg_buf,
620 dev->iamthif_msg_buf_index);
621 list_add_tail(&cb->list, &dev->amthif_rd_complete_list.list);
622 dev_dbg(&dev->pdev->dev, "amthif read completed\n");
623 dev->iamthif_timer = jiffies;
624 dev_dbg(&dev->pdev->dev, "dev->iamthif_timer = %ld\n",
627 mei_amthif_run_next_cmd(dev);
630 dev_dbg(&dev->pdev->dev, "completing amthif call back.\n");
631 wake_up_interruptible(&dev->iamthif_cl.wait);
635 * mei_clear_list - removes all callbacks associated with file
638 * @dev: device structure.
639 * @file: file structure
640 * @mei_cb_list: callbacks list
642 * mei_clear_list is called to clear resources associated with file
643 * when application calls close function or Ctrl-C was pressed
645 * returns true if callback removed from the list, false otherwise
647 static bool mei_clear_list(struct mei_device *dev,
648 const struct file *file, struct list_head *mei_cb_list)
650 struct mei_cl_cb *cb_pos = NULL;
651 struct mei_cl_cb *cb_next = NULL;
652 bool removed = false;
654 /* list all list member */
655 list_for_each_entry_safe(cb_pos, cb_next, mei_cb_list, list) {
656 /* check if list member associated with a file */
657 if (file == cb_pos->file_object) {
658 /* remove member from the list */
659 list_del(&cb_pos->list);
660 /* check if cb equal to current iamthif cb */
661 if (dev->iamthif_current_cb == cb_pos) {
662 dev->iamthif_current_cb = NULL;
663 /* send flow control to iamthif client */
664 mei_hbm_cl_flow_control_req(dev,
667 /* free all allocated buffers */
668 mei_io_cb_free(cb_pos);
677 * mei_clear_lists - removes all callbacks associated with file
679 * @dev: device structure
680 * @file: file structure
682 * mei_clear_lists is called to clear resources associated with file
683 * when application calls close function or Ctrl-C was pressed
685 * returns true if callback removed from the list, false otherwise
687 static bool mei_clear_lists(struct mei_device *dev, struct file *file)
689 bool removed = false;
691 /* remove callbacks associated with a file */
692 mei_clear_list(dev, file, &dev->amthif_cmd_list.list);
693 if (mei_clear_list(dev, file, &dev->amthif_rd_complete_list.list))
696 mei_clear_list(dev, file, &dev->ctrl_rd_list.list);
698 if (mei_clear_list(dev, file, &dev->ctrl_wr_list.list))
701 if (mei_clear_list(dev, file, &dev->write_waiting_list.list))
704 if (mei_clear_list(dev, file, &dev->write_list.list))
707 /* check if iamthif_current_cb not NULL */
708 if (dev->iamthif_current_cb && !removed) {
709 /* check file and iamthif current cb association */
710 if (dev->iamthif_current_cb->file_object == file) {
712 mei_io_cb_free(dev->iamthif_current_cb);
713 dev->iamthif_current_cb = NULL;
721 * mei_amthif_release - the release function
723 * @dev: device structure
724 * @file: pointer to file structure
726 * returns 0 on success, <0 on error
728 int mei_amthif_release(struct mei_device *dev, struct file *file)
730 if (dev->iamthif_open_count > 0)
731 dev->iamthif_open_count--;
733 if (dev->iamthif_file_object == file &&
734 dev->iamthif_state != MEI_IAMTHIF_IDLE) {
736 dev_dbg(&dev->pdev->dev, "amthif canceled iamthif state %d\n",
738 dev->iamthif_canceled = true;
739 if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE) {
740 dev_dbg(&dev->pdev->dev, "run next amthif iamthif cb\n");
741 mei_amthif_run_next_cmd(dev);
745 if (mei_clear_lists(dev, file))
746 dev->iamthif_state = MEI_IAMTHIF_IDLE;