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>
39 const uuid_le mei_amthif_guid = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d,
40 0xac, 0xa8, 0x46, 0xe0,
41 0xff, 0x65, 0x81, 0x4c);
44 * mei_amthif_reset_params - initializes mei device iamthif
46 * @dev: the device structure
48 void mei_amthif_reset_params(struct mei_device *dev)
50 /* reset iamthif parameters. */
51 dev->iamthif_current_cb = NULL;
52 dev->iamthif_msg_buf_size = 0;
53 dev->iamthif_msg_buf_index = 0;
54 dev->iamthif_canceled = false;
55 dev->iamthif_ioctl = false;
56 dev->iamthif_state = MEI_IAMTHIF_IDLE;
57 dev->iamthif_timer = 0;
58 dev->iamthif_stall_timer = 0;
59 dev->iamthif_open_count = 0;
63 * mei_amthif_host_init - mei initialization amthif client.
65 * @dev: the device structure
68 int mei_amthif_host_init(struct mei_device *dev)
70 struct mei_cl *cl = &dev->iamthif_cl;
71 unsigned char *msg_buf;
74 dev->iamthif_state = MEI_IAMTHIF_IDLE;
78 i = mei_me_cl_by_uuid(dev, &mei_amthif_guid);
80 dev_info(&dev->pdev->dev,
81 "amthif: failed to find the client %d\n", i);
85 cl->me_client_id = dev->me_clients[i].client_id;
87 /* Assign iamthif_mtu to the value received from ME */
89 dev->iamthif_mtu = dev->me_clients[i].props.max_msg_length;
90 dev_dbg(&dev->pdev->dev, "IAMTHIF_MTU = %d\n",
91 dev->me_clients[i].props.max_msg_length);
93 kfree(dev->iamthif_msg_buf);
94 dev->iamthif_msg_buf = NULL;
96 /* allocate storage for ME message buffer */
97 msg_buf = kcalloc(dev->iamthif_mtu,
98 sizeof(unsigned char), GFP_KERNEL);
100 dev_err(&dev->pdev->dev, "amthif: memory allocation for ME message buffer failed.\n");
104 dev->iamthif_msg_buf = msg_buf;
106 ret = mei_cl_link(cl, MEI_IAMTHIF_HOST_CLIENT_ID);
109 dev_err(&dev->pdev->dev,
110 "amthif: failed link client %d\n", ret);
114 ret = mei_cl_connect(cl, NULL);
116 dev->iamthif_state = MEI_IAMTHIF_IDLE;
122 * mei_amthif_find_read_list_entry - finds a amthilist entry for current file
124 * @dev: the device structure
125 * @file: pointer to file object
127 * returns returned a list entry on success, NULL on failure.
129 struct mei_cl_cb *mei_amthif_find_read_list_entry(struct mei_device *dev,
132 struct mei_cl_cb *cb;
134 list_for_each_entry(cb, &dev->amthif_rd_complete_list.list, list) {
135 if (cb->cl && cb->cl == &dev->iamthif_cl &&
136 cb->file_object == file)
144 * mei_amthif_read - read data from AMTHIF client
146 * @dev: the device structure
147 * @if_num: minor number
148 * @file: pointer to file object
149 * @*ubuf: pointer to user data in user space
150 * @length: data length to read
151 * @offset: data read offset
153 * Locking: called under "dev->device_lock" lock
156 * returned data length on success,
157 * zero if no data to read,
158 * negative on failure.
160 int mei_amthif_read(struct mei_device *dev, struct file *file,
161 char __user *ubuf, size_t length, loff_t *offset)
165 struct mei_cl_cb *cb = NULL;
166 struct mei_cl *cl = file->private_data;
167 unsigned long timeout;
170 /* Only possible if we are in timeout */
171 if (!cl || cl != &dev->iamthif_cl) {
172 dev_dbg(&dev->pdev->dev, "bad file ext.\n");
176 i = mei_me_cl_by_id(dev, dev->iamthif_cl.me_client_id);
178 dev_dbg(&dev->pdev->dev, "amthif client not found.\n");
181 dev_dbg(&dev->pdev->dev, "checking amthif data\n");
182 cb = mei_amthif_find_read_list_entry(dev, file);
184 /* Check for if we can block or not*/
185 if (cb == NULL && file->f_flags & O_NONBLOCK)
189 dev_dbg(&dev->pdev->dev, "waiting for amthif data\n");
191 /* unlock the Mutex */
192 mutex_unlock(&dev->device_lock);
194 wait_ret = wait_event_interruptible(dev->iamthif_cl.wait,
195 (cb = mei_amthif_find_read_list_entry(dev, file)));
197 /* Locking again the Mutex */
198 mutex_lock(&dev->device_lock);
203 dev_dbg(&dev->pdev->dev, "woke up from sleep\n");
207 dev_dbg(&dev->pdev->dev, "Got amthif data\n");
208 dev->iamthif_timer = 0;
211 timeout = cb->read_time +
212 mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
213 dev_dbg(&dev->pdev->dev, "amthif timeout = %lud\n",
216 if (time_after(jiffies, timeout)) {
217 dev_dbg(&dev->pdev->dev, "amthif Time out\n");
218 /* 15 sec for the message has expired */
224 /* if the whole message will fit remove it from the list */
225 if (cb->buf_idx >= *offset && length >= (cb->buf_idx - *offset))
227 else if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
228 /* end of the message has been reached */
233 /* else means that not full buffer will be read and do not
234 * remove message from deletion list
237 dev_dbg(&dev->pdev->dev, "amthif cb->response_buffer size - %d\n",
238 cb->response_buffer.size);
239 dev_dbg(&dev->pdev->dev, "amthif cb->buf_idx - %lu\n", cb->buf_idx);
241 /* length is being truncated to PAGE_SIZE, however,
242 * the buf_idx may point beyond */
243 length = min_t(size_t, length, (cb->buf_idx - *offset));
245 if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
246 dev_dbg(&dev->pdev->dev, "failed to copy data to userland\n");
250 if ((*offset + length) < cb->buf_idx) {
256 dev_dbg(&dev->pdev->dev, "free amthif cb memory.\n");
264 * mei_amthif_send_cmd - send amthif command to the ME
266 * @dev: the device structure
267 * @cb: mei call back struct
269 * returns 0 on success, <0 on failure.
272 static int mei_amthif_send_cmd(struct mei_device *dev, struct mei_cl_cb *cb)
274 struct mei_msg_hdr mei_hdr;
280 dev_dbg(&dev->pdev->dev, "write data to amthif client.\n");
282 dev->iamthif_state = MEI_IAMTHIF_WRITING;
283 dev->iamthif_current_cb = cb;
284 dev->iamthif_file_object = cb->file_object;
285 dev->iamthif_canceled = false;
286 dev->iamthif_ioctl = true;
287 dev->iamthif_msg_buf_size = cb->request_buffer.size;
288 memcpy(dev->iamthif_msg_buf, cb->request_buffer.data,
289 cb->request_buffer.size);
291 ret = mei_cl_flow_ctrl_creds(&dev->iamthif_cl);
295 if (ret && mei_hbuf_acquire(dev)) {
297 if (cb->request_buffer.size > mei_hbuf_max_len(dev)) {
298 mei_hdr.length = mei_hbuf_max_len(dev);
299 mei_hdr.msg_complete = 0;
301 mei_hdr.length = cb->request_buffer.size;
302 mei_hdr.msg_complete = 1;
305 mei_hdr.host_addr = dev->iamthif_cl.host_client_id;
306 mei_hdr.me_addr = dev->iamthif_cl.me_client_id;
307 mei_hdr.reserved = 0;
308 mei_hdr.internal = 0;
309 dev->iamthif_msg_buf_index += mei_hdr.length;
310 ret = mei_write_message(dev, &mei_hdr, dev->iamthif_msg_buf);
314 if (mei_hdr.msg_complete) {
315 if (mei_cl_flow_ctrl_reduce(&dev->iamthif_cl))
317 dev->iamthif_flow_control_pending = true;
318 dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
319 dev_dbg(&dev->pdev->dev, "add amthif cb to write waiting list\n");
320 dev->iamthif_current_cb = cb;
321 dev->iamthif_file_object = cb->file_object;
322 list_add_tail(&cb->list, &dev->write_waiting_list.list);
324 dev_dbg(&dev->pdev->dev, "message does not complete, so add amthif cb to write list.\n");
325 list_add_tail(&cb->list, &dev->write_list.list);
328 list_add_tail(&cb->list, &dev->write_list.list);
334 * mei_amthif_write - write amthif data to amthif client
336 * @dev: the device structure
337 * @cb: mei call back struct
339 * returns 0 on success, <0 on failure.
342 int mei_amthif_write(struct mei_device *dev, struct mei_cl_cb *cb)
349 ret = mei_io_cb_alloc_resp_buf(cb, dev->iamthif_mtu);
353 cb->fop_type = MEI_FOP_WRITE;
355 if (!list_empty(&dev->amthif_cmd_list.list) ||
356 dev->iamthif_state != MEI_IAMTHIF_IDLE) {
357 dev_dbg(&dev->pdev->dev,
358 "amthif state = %d\n", dev->iamthif_state);
359 dev_dbg(&dev->pdev->dev, "AMTHIF: add cb to the wait list\n");
360 list_add_tail(&cb->list, &dev->amthif_cmd_list.list);
363 return mei_amthif_send_cmd(dev, cb);
366 * mei_amthif_run_next_cmd
368 * @dev: the device structure
370 * returns 0 on success, <0 on failure.
372 void mei_amthif_run_next_cmd(struct mei_device *dev)
374 struct mei_cl_cb *pos = NULL;
375 struct mei_cl_cb *next = NULL;
381 dev->iamthif_msg_buf_size = 0;
382 dev->iamthif_msg_buf_index = 0;
383 dev->iamthif_canceled = false;
384 dev->iamthif_ioctl = true;
385 dev->iamthif_state = MEI_IAMTHIF_IDLE;
386 dev->iamthif_timer = 0;
387 dev->iamthif_file_object = NULL;
389 dev_dbg(&dev->pdev->dev, "complete amthif cmd_list cb.\n");
391 list_for_each_entry_safe(pos, next, &dev->amthif_cmd_list.list, list) {
392 list_del(&pos->list);
394 if (pos->cl && pos->cl == &dev->iamthif_cl) {
395 status = mei_amthif_send_cmd(dev, pos);
397 dev_dbg(&dev->pdev->dev,
398 "amthif write failed status = %d\n",
408 unsigned int mei_amthif_poll(struct mei_device *dev,
409 struct file *file, poll_table *wait)
411 unsigned int mask = 0;
413 poll_wait(file, &dev->iamthif_cl.wait, wait);
415 mutex_lock(&dev->device_lock);
416 if (!mei_cl_is_connected(&dev->iamthif_cl)) {
420 } else if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE &&
421 dev->iamthif_file_object == file) {
423 mask |= (POLLIN | POLLRDNORM);
424 dev_dbg(&dev->pdev->dev, "run next amthif cb\n");
425 mei_amthif_run_next_cmd(dev);
427 mutex_unlock(&dev->device_lock);
435 * mei_amthif_irq_write - write iamthif command in irq thread context.
437 * @dev: the device structure.
438 * @cb_pos: callback block.
439 * @cl: private data of the file object.
440 * @cmpl_list: complete list.
442 * returns 0, OK; otherwise, error.
444 int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
445 struct mei_cl_cb *cmpl_list)
447 struct mei_device *dev = cl->dev;
448 struct mei_msg_hdr mei_hdr;
449 size_t len = dev->iamthif_msg_buf_size - dev->iamthif_msg_buf_index;
450 u32 msg_slots = mei_data2slots(len);
454 rets = mei_cl_flow_ctrl_creds(cl);
459 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
463 mei_hdr.host_addr = cl->host_client_id;
464 mei_hdr.me_addr = cl->me_client_id;
465 mei_hdr.reserved = 0;
466 mei_hdr.internal = 0;
468 slots = mei_hbuf_empty_slots(dev);
470 if (slots >= msg_slots) {
471 mei_hdr.length = len;
472 mei_hdr.msg_complete = 1;
473 /* Split the message only if we can write the whole host buffer */
474 } else if (slots == dev->hbuf_depth) {
476 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
477 mei_hdr.length = len;
478 mei_hdr.msg_complete = 0;
480 /* wait for next time the host buffer is empty */
484 dev_dbg(&dev->pdev->dev, MEI_HDR_FMT, MEI_HDR_PRM(&mei_hdr));
486 rets = mei_write_message(dev, &mei_hdr,
487 dev->iamthif_msg_buf + dev->iamthif_msg_buf_index);
489 dev->iamthif_state = MEI_IAMTHIF_IDLE;
495 if (mei_cl_flow_ctrl_reduce(cl))
498 dev->iamthif_msg_buf_index += mei_hdr.length;
501 if (mei_hdr.msg_complete) {
502 dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
503 dev->iamthif_flow_control_pending = true;
505 /* save iamthif cb sent to amthif client */
506 cb->buf_idx = dev->iamthif_msg_buf_index;
507 dev->iamthif_current_cb = cb;
509 list_move_tail(&cb->list, &dev->write_waiting_list.list);
517 * mei_amthif_irq_read_message - read routine after ISR to
518 * handle the read amthif message
520 * @dev: the device structure
521 * @mei_hdr: header of amthif message
522 * @complete_list: An instance of our list structure
524 * returns 0 on success, <0 on failure.
526 int mei_amthif_irq_read_msg(struct mei_device *dev,
527 struct mei_msg_hdr *mei_hdr,
528 struct mei_cl_cb *complete_list)
530 struct mei_cl_cb *cb;
531 unsigned char *buffer;
533 BUG_ON(mei_hdr->me_addr != dev->iamthif_cl.me_client_id);
534 BUG_ON(dev->iamthif_state != MEI_IAMTHIF_READING);
536 buffer = dev->iamthif_msg_buf + dev->iamthif_msg_buf_index;
537 BUG_ON(dev->iamthif_mtu < dev->iamthif_msg_buf_index + mei_hdr->length);
539 mei_read_slots(dev, buffer, mei_hdr->length);
541 dev->iamthif_msg_buf_index += mei_hdr->length;
543 if (!mei_hdr->msg_complete)
546 dev_dbg(&dev->pdev->dev, "amthif_message_buffer_index =%d\n",
549 dev_dbg(&dev->pdev->dev, "completed amthif read.\n ");
550 if (!dev->iamthif_current_cb)
553 cb = dev->iamthif_current_cb;
554 dev->iamthif_current_cb = NULL;
559 dev->iamthif_stall_timer = 0;
560 cb->buf_idx = dev->iamthif_msg_buf_index;
561 cb->read_time = jiffies;
562 if (dev->iamthif_ioctl && cb->cl == &dev->iamthif_cl) {
563 /* found the iamthif cb */
564 dev_dbg(&dev->pdev->dev, "complete the amthif read cb.\n ");
565 dev_dbg(&dev->pdev->dev, "add the amthif read cb to complete.\n ");
566 list_add_tail(&cb->list, &complete_list->list);
572 * mei_amthif_irq_read - prepares to read amthif data.
574 * @dev: the device structure.
575 * @slots: free slots.
577 * returns 0, OK; otherwise, error.
579 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots)
581 u32 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
583 if (*slots < msg_slots)
588 if (mei_hbm_cl_flow_control_req(dev, &dev->iamthif_cl)) {
589 dev_dbg(&dev->pdev->dev, "iamthif flow control failed\n");
593 dev_dbg(&dev->pdev->dev, "iamthif flow control success\n");
594 dev->iamthif_state = MEI_IAMTHIF_READING;
595 dev->iamthif_flow_control_pending = false;
596 dev->iamthif_msg_buf_index = 0;
597 dev->iamthif_msg_buf_size = 0;
598 dev->iamthif_stall_timer = MEI_IAMTHIF_STALL_TIMER;
599 dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
604 * mei_amthif_complete - complete amthif callback.
606 * @dev: the device structure.
607 * @cb_pos: callback block.
609 void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb)
611 if (dev->iamthif_canceled != 1) {
612 dev->iamthif_state = MEI_IAMTHIF_READ_COMPLETE;
613 dev->iamthif_stall_timer = 0;
614 memcpy(cb->response_buffer.data,
615 dev->iamthif_msg_buf,
616 dev->iamthif_msg_buf_index);
617 list_add_tail(&cb->list, &dev->amthif_rd_complete_list.list);
618 dev_dbg(&dev->pdev->dev, "amthif read completed\n");
619 dev->iamthif_timer = jiffies;
620 dev_dbg(&dev->pdev->dev, "dev->iamthif_timer = %ld\n",
623 mei_amthif_run_next_cmd(dev);
626 dev_dbg(&dev->pdev->dev, "completing amthif call back.\n");
627 wake_up_interruptible(&dev->iamthif_cl.wait);
631 * mei_clear_list - removes all callbacks associated with file
634 * @dev: device structure.
635 * @file: file structure
636 * @mei_cb_list: callbacks list
638 * mei_clear_list is called to clear resources associated with file
639 * when application calls close function or Ctrl-C was pressed
641 * returns true if callback removed from the list, false otherwise
643 static bool mei_clear_list(struct mei_device *dev,
644 const struct file *file, struct list_head *mei_cb_list)
646 struct mei_cl_cb *cb_pos = NULL;
647 struct mei_cl_cb *cb_next = NULL;
648 bool removed = false;
650 /* list all list member */
651 list_for_each_entry_safe(cb_pos, cb_next, mei_cb_list, list) {
652 /* check if list member associated with a file */
653 if (file == cb_pos->file_object) {
654 /* remove member from the list */
655 list_del(&cb_pos->list);
656 /* check if cb equal to current iamthif cb */
657 if (dev->iamthif_current_cb == cb_pos) {
658 dev->iamthif_current_cb = NULL;
659 /* send flow control to iamthif client */
660 mei_hbm_cl_flow_control_req(dev,
663 /* free all allocated buffers */
664 mei_io_cb_free(cb_pos);
673 * mei_clear_lists - removes all callbacks associated with file
675 * @dev: device structure
676 * @file: file structure
678 * mei_clear_lists is called to clear resources associated with file
679 * when application calls close function or Ctrl-C was pressed
681 * returns true if callback removed from the list, false otherwise
683 static bool mei_clear_lists(struct mei_device *dev, struct file *file)
685 bool removed = false;
687 /* remove callbacks associated with a file */
688 mei_clear_list(dev, file, &dev->amthif_cmd_list.list);
689 if (mei_clear_list(dev, file, &dev->amthif_rd_complete_list.list))
692 mei_clear_list(dev, file, &dev->ctrl_rd_list.list);
694 if (mei_clear_list(dev, file, &dev->ctrl_wr_list.list))
697 if (mei_clear_list(dev, file, &dev->write_waiting_list.list))
700 if (mei_clear_list(dev, file, &dev->write_list.list))
703 /* check if iamthif_current_cb not NULL */
704 if (dev->iamthif_current_cb && !removed) {
705 /* check file and iamthif current cb association */
706 if (dev->iamthif_current_cb->file_object == file) {
708 mei_io_cb_free(dev->iamthif_current_cb);
709 dev->iamthif_current_cb = NULL;
717 * mei_amthif_release - the release function
719 * @dev: device structure
720 * @file: pointer to file structure
722 * returns 0 on success, <0 on error
724 int mei_amthif_release(struct mei_device *dev, struct file *file)
726 if (dev->iamthif_open_count > 0)
727 dev->iamthif_open_count--;
729 if (dev->iamthif_file_object == file &&
730 dev->iamthif_state != MEI_IAMTHIF_IDLE) {
732 dev_dbg(&dev->pdev->dev, "amthif canceled iamthif state %d\n",
734 dev->iamthif_canceled = true;
735 if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE) {
736 dev_dbg(&dev->pdev->dev, "run next amthif iamthif cb\n");
737 mei_amthif_run_next_cmd(dev);
741 if (mei_clear_lists(dev, file))
742 dev->iamthif_state = MEI_IAMTHIF_IDLE;