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/ioctl.h>
24 #include <linux/cdev.h>
25 #include <linux/list.h>
26 #include <linux/delay.h>
27 #include <linux/sched.h>
28 #include <linux/uuid.h>
29 #include <linux/jiffies.h>
30 #include <linux/uaccess.h>
31 #include <linux/slab.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
67 * Return: 0 on success, <0 on failure.
69 int mei_amthif_host_init(struct mei_device *dev)
71 struct mei_cl *cl = &dev->iamthif_cl;
72 struct mei_me_client *me_cl;
73 unsigned char *msg_buf;
76 dev->iamthif_state = MEI_IAMTHIF_IDLE;
80 me_cl = mei_me_cl_by_uuid(dev, &mei_amthif_guid);
82 dev_info(dev->dev, "amthif: failed to find the client");
86 cl->me_client_id = me_cl->client_id;
87 cl->cl_uuid = me_cl->props.protocol_name;
89 /* Assign iamthif_mtu to the value received from ME */
91 dev->iamthif_mtu = me_cl->props.max_msg_length;
92 dev_dbg(dev->dev, "IAMTHIF_MTU = %d\n", dev->iamthif_mtu);
94 kfree(dev->iamthif_msg_buf);
95 dev->iamthif_msg_buf = NULL;
97 /* allocate storage for ME message buffer */
98 msg_buf = kcalloc(dev->iamthif_mtu,
99 sizeof(unsigned char), GFP_KERNEL);
105 dev->iamthif_msg_buf = msg_buf;
107 ret = mei_cl_link(cl, MEI_IAMTHIF_HOST_CLIENT_ID);
109 dev_err(dev->dev, "amthif: failed cl_link %d\n", ret);
113 ret = mei_cl_connect(cl, NULL);
115 dev->iamthif_state = MEI_IAMTHIF_IDLE;
118 mei_me_cl_put(me_cl);
123 * mei_amthif_find_read_list_entry - finds a amthilist entry for current file
125 * @dev: the device structure
126 * @file: pointer to file object
128 * Return: returned a list entry on success, NULL on failure.
130 struct mei_cl_cb *mei_amthif_find_read_list_entry(struct mei_device *dev,
133 struct mei_cl_cb *cb;
135 list_for_each_entry(cb, &dev->amthif_rd_complete_list.list, list)
136 if (cb->file_object == file)
143 * mei_amthif_read - read data from AMTHIF client
145 * @dev: the device structure
146 * @file: pointer to file object
147 * @ubuf: pointer to user data in user space
148 * @length: data length to read
149 * @offset: data read offset
151 * Locking: called under "dev->device_lock" lock
154 * returned data length on success,
155 * zero if no data to read,
156 * negative on failure.
158 int mei_amthif_read(struct mei_device *dev, struct file *file,
159 char __user *ubuf, size_t length, loff_t *offset)
161 struct mei_cl *cl = file->private_data;
162 struct mei_cl_cb *cb;
163 unsigned long timeout;
167 /* Only possible if we are in timeout */
169 dev_err(dev->dev, "bad file ext.\n");
173 dev_dbg(dev->dev, "checking amthif data\n");
174 cb = mei_amthif_find_read_list_entry(dev, file);
176 /* Check for if we can block or not*/
177 if (cb == NULL && file->f_flags & O_NONBLOCK)
181 dev_dbg(dev->dev, "waiting for amthif data\n");
183 /* unlock the Mutex */
184 mutex_unlock(&dev->device_lock);
186 wait_ret = wait_event_interruptible(dev->iamthif_cl.wait,
187 (cb = mei_amthif_find_read_list_entry(dev, file)));
189 /* Locking again the Mutex */
190 mutex_lock(&dev->device_lock);
195 dev_dbg(dev->dev, "woke up from sleep\n");
199 dev_dbg(dev->dev, "Got amthif data\n");
200 dev->iamthif_timer = 0;
203 timeout = cb->read_time +
204 mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
205 dev_dbg(dev->dev, "amthif timeout = %lud\n",
208 if (time_after(jiffies, timeout)) {
209 dev_dbg(dev->dev, "amthif Time out\n");
210 /* 15 sec for the message has expired */
216 /* if the whole message will fit remove it from the list */
217 if (cb->buf_idx >= *offset && length >= (cb->buf_idx - *offset))
219 else if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
220 /* end of the message has been reached */
225 /* else means that not full buffer will be read and do not
226 * remove message from deletion list
229 dev_dbg(dev->dev, "amthif cb->response_buffer size - %d\n",
230 cb->response_buffer.size);
231 dev_dbg(dev->dev, "amthif cb->buf_idx - %lu\n", cb->buf_idx);
233 /* length is being truncated to PAGE_SIZE, however,
234 * the buf_idx may point beyond */
235 length = min_t(size_t, length, (cb->buf_idx - *offset));
237 if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length)) {
238 dev_dbg(dev->dev, "failed to copy data to userland\n");
242 if ((*offset + length) < cb->buf_idx) {
248 dev_dbg(dev->dev, "free amthif cb memory.\n");
256 * mei_amthif_send_cmd - send amthif command to the ME
258 * @dev: the device structure
259 * @cb: mei call back struct
261 * Return: 0 on success, <0 on failure.
264 static int mei_amthif_send_cmd(struct mei_device *dev, struct mei_cl_cb *cb)
266 struct mei_msg_hdr mei_hdr;
273 dev_dbg(dev->dev, "write data to amthif client.\n");
275 dev->iamthif_state = MEI_IAMTHIF_WRITING;
276 dev->iamthif_current_cb = cb;
277 dev->iamthif_file_object = cb->file_object;
278 dev->iamthif_canceled = false;
279 dev->iamthif_ioctl = true;
280 dev->iamthif_msg_buf_size = cb->request_buffer.size;
281 memcpy(dev->iamthif_msg_buf, cb->request_buffer.data,
282 cb->request_buffer.size);
283 cl = &dev->iamthif_cl;
285 ret = mei_cl_flow_ctrl_creds(cl);
289 if (ret && mei_hbuf_acquire(dev)) {
291 if (cb->request_buffer.size > mei_hbuf_max_len(dev)) {
292 mei_hdr.length = mei_hbuf_max_len(dev);
293 mei_hdr.msg_complete = 0;
295 mei_hdr.length = cb->request_buffer.size;
296 mei_hdr.msg_complete = 1;
299 mei_hdr.host_addr = cl->host_client_id;
300 mei_hdr.me_addr = cl->me_client_id;
301 mei_hdr.reserved = 0;
302 mei_hdr.internal = 0;
303 dev->iamthif_msg_buf_index += mei_hdr.length;
304 ret = mei_write_message(dev, &mei_hdr, dev->iamthif_msg_buf);
308 if (mei_hdr.msg_complete) {
309 if (mei_cl_flow_ctrl_reduce(cl))
311 dev->iamthif_flow_control_pending = true;
312 dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
313 dev_dbg(dev->dev, "add amthif cb to write waiting list\n");
314 dev->iamthif_current_cb = cb;
315 dev->iamthif_file_object = cb->file_object;
316 list_add_tail(&cb->list, &dev->write_waiting_list.list);
318 dev_dbg(dev->dev, "message does not complete, so add amthif cb to write list.\n");
319 list_add_tail(&cb->list, &dev->write_list.list);
322 list_add_tail(&cb->list, &dev->write_list.list);
328 * mei_amthif_write - write amthif data to amthif client
330 * @dev: the device structure
331 * @cb: mei call back struct
333 * Return: 0 on success, <0 on failure.
336 int mei_amthif_write(struct mei_device *dev, struct mei_cl_cb *cb)
343 ret = mei_io_cb_alloc_resp_buf(cb, dev->iamthif_mtu);
347 cb->fop_type = MEI_FOP_WRITE;
349 if (!list_empty(&dev->amthif_cmd_list.list) ||
350 dev->iamthif_state != MEI_IAMTHIF_IDLE) {
352 "amthif state = %d\n", dev->iamthif_state);
353 dev_dbg(dev->dev, "AMTHIF: add cb to the wait list\n");
354 list_add_tail(&cb->list, &dev->amthif_cmd_list.list);
357 return mei_amthif_send_cmd(dev, cb);
360 * mei_amthif_run_next_cmd - send next amt command from queue
362 * @dev: the device structure
364 void mei_amthif_run_next_cmd(struct mei_device *dev)
366 struct mei_cl_cb *cb;
372 dev->iamthif_msg_buf_size = 0;
373 dev->iamthif_msg_buf_index = 0;
374 dev->iamthif_canceled = false;
375 dev->iamthif_ioctl = true;
376 dev->iamthif_state = MEI_IAMTHIF_IDLE;
377 dev->iamthif_timer = 0;
378 dev->iamthif_file_object = NULL;
380 dev_dbg(dev->dev, "complete amthif cmd_list cb.\n");
382 cb = list_first_entry_or_null(&dev->amthif_cmd_list.list,
387 ret = mei_amthif_send_cmd(dev, cb);
389 dev_warn(dev->dev, "amthif write failed status = %d\n", ret);
393 unsigned int mei_amthif_poll(struct mei_device *dev,
394 struct file *file, poll_table *wait)
396 unsigned int mask = 0;
398 poll_wait(file, &dev->iamthif_cl.wait, wait);
400 mutex_lock(&dev->device_lock);
401 if (!mei_cl_is_connected(&dev->iamthif_cl)) {
405 } else if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE &&
406 dev->iamthif_file_object == file) {
408 mask |= (POLLIN | POLLRDNORM);
409 dev_dbg(dev->dev, "run next amthif cb\n");
410 mei_amthif_run_next_cmd(dev);
412 mutex_unlock(&dev->device_lock);
420 * mei_amthif_irq_write - write iamthif command in irq thread context.
422 * @cl: private data of the file object.
423 * @cb: callback block.
424 * @cmpl_list: complete list.
426 * Return: 0, OK; otherwise, error.
428 int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
429 struct mei_cl_cb *cmpl_list)
431 struct mei_device *dev = cl->dev;
432 struct mei_msg_hdr mei_hdr;
433 size_t len = dev->iamthif_msg_buf_size - dev->iamthif_msg_buf_index;
434 u32 msg_slots = mei_data2slots(len);
438 rets = mei_cl_flow_ctrl_creds(cl);
443 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
447 mei_hdr.host_addr = cl->host_client_id;
448 mei_hdr.me_addr = cl->me_client_id;
449 mei_hdr.reserved = 0;
450 mei_hdr.internal = 0;
452 slots = mei_hbuf_empty_slots(dev);
454 if (slots >= msg_slots) {
455 mei_hdr.length = len;
456 mei_hdr.msg_complete = 1;
457 /* Split the message only if we can write the whole host buffer */
458 } else if (slots == dev->hbuf_depth) {
460 len = (slots * sizeof(u32)) - sizeof(struct mei_msg_hdr);
461 mei_hdr.length = len;
462 mei_hdr.msg_complete = 0;
464 /* wait for next time the host buffer is empty */
468 dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(&mei_hdr));
470 rets = mei_write_message(dev, &mei_hdr,
471 dev->iamthif_msg_buf + dev->iamthif_msg_buf_index);
473 dev->iamthif_state = MEI_IAMTHIF_IDLE;
479 if (mei_cl_flow_ctrl_reduce(cl))
482 dev->iamthif_msg_buf_index += mei_hdr.length;
485 if (mei_hdr.msg_complete) {
486 dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
487 dev->iamthif_flow_control_pending = true;
489 /* save iamthif cb sent to amthif client */
490 cb->buf_idx = dev->iamthif_msg_buf_index;
491 dev->iamthif_current_cb = cb;
493 list_move_tail(&cb->list, &dev->write_waiting_list.list);
501 * mei_amthif_irq_read_msg - read routine after ISR to
502 * handle the read amthif message
504 * @dev: the device structure
505 * @mei_hdr: header of amthif message
506 * @complete_list: An instance of our list structure
508 * Return: 0 on success, <0 on failure.
510 int mei_amthif_irq_read_msg(struct mei_device *dev,
511 struct mei_msg_hdr *mei_hdr,
512 struct mei_cl_cb *complete_list)
514 struct mei_cl_cb *cb;
515 unsigned char *buffer;
517 BUG_ON(mei_hdr->me_addr != dev->iamthif_cl.me_client_id);
518 BUG_ON(dev->iamthif_state != MEI_IAMTHIF_READING);
520 buffer = dev->iamthif_msg_buf + dev->iamthif_msg_buf_index;
521 BUG_ON(dev->iamthif_mtu < dev->iamthif_msg_buf_index + mei_hdr->length);
523 mei_read_slots(dev, buffer, mei_hdr->length);
525 dev->iamthif_msg_buf_index += mei_hdr->length;
527 if (!mei_hdr->msg_complete)
530 dev_dbg(dev->dev, "amthif_message_buffer_index =%d\n",
533 dev_dbg(dev->dev, "completed amthif read.\n ");
534 if (!dev->iamthif_current_cb)
537 cb = dev->iamthif_current_cb;
538 dev->iamthif_current_cb = NULL;
540 dev->iamthif_stall_timer = 0;
541 cb->buf_idx = dev->iamthif_msg_buf_index;
542 cb->read_time = jiffies;
543 if (dev->iamthif_ioctl) {
544 /* found the iamthif cb */
545 dev_dbg(dev->dev, "complete the amthif read cb.\n ");
546 dev_dbg(dev->dev, "add the amthif read cb to complete.\n ");
547 list_add_tail(&cb->list, &complete_list->list);
553 * mei_amthif_irq_read - prepares to read amthif data.
555 * @dev: the device structure.
556 * @slots: free slots.
558 * Return: 0, OK; otherwise, error.
560 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots)
562 u32 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
564 if (*slots < msg_slots)
569 if (mei_hbm_cl_flow_control_req(dev, &dev->iamthif_cl)) {
570 dev_dbg(dev->dev, "iamthif flow control failed\n");
574 dev_dbg(dev->dev, "iamthif flow control success\n");
575 dev->iamthif_state = MEI_IAMTHIF_READING;
576 dev->iamthif_flow_control_pending = false;
577 dev->iamthif_msg_buf_index = 0;
578 dev->iamthif_msg_buf_size = 0;
579 dev->iamthif_stall_timer = MEI_IAMTHIF_STALL_TIMER;
580 dev->hbuf_is_ready = mei_hbuf_is_ready(dev);
585 * mei_amthif_complete - complete amthif callback.
587 * @dev: the device structure.
588 * @cb: callback block.
590 void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb)
592 if (dev->iamthif_canceled != 1) {
593 dev->iamthif_state = MEI_IAMTHIF_READ_COMPLETE;
594 dev->iamthif_stall_timer = 0;
595 memcpy(cb->response_buffer.data,
596 dev->iamthif_msg_buf,
597 dev->iamthif_msg_buf_index);
598 list_add_tail(&cb->list, &dev->amthif_rd_complete_list.list);
599 dev_dbg(dev->dev, "amthif read completed\n");
600 dev->iamthif_timer = jiffies;
601 dev_dbg(dev->dev, "dev->iamthif_timer = %ld\n",
604 mei_amthif_run_next_cmd(dev);
607 dev_dbg(dev->dev, "completing amthif call back.\n");
608 wake_up_interruptible(&dev->iamthif_cl.wait);
612 * mei_clear_list - removes all callbacks associated with file
615 * @dev: device structure.
616 * @file: file structure
617 * @mei_cb_list: callbacks list
619 * mei_clear_list is called to clear resources associated with file
620 * when application calls close function or Ctrl-C was pressed
622 * Return: true if callback removed from the list, false otherwise
624 static bool mei_clear_list(struct mei_device *dev,
625 const struct file *file, struct list_head *mei_cb_list)
627 struct mei_cl_cb *cb_pos = NULL;
628 struct mei_cl_cb *cb_next = NULL;
629 bool removed = false;
631 /* list all list member */
632 list_for_each_entry_safe(cb_pos, cb_next, mei_cb_list, list) {
633 /* check if list member associated with a file */
634 if (file == cb_pos->file_object) {
635 /* remove member from the list */
636 list_del(&cb_pos->list);
637 /* check if cb equal to current iamthif cb */
638 if (dev->iamthif_current_cb == cb_pos) {
639 dev->iamthif_current_cb = NULL;
640 /* send flow control to iamthif client */
641 mei_hbm_cl_flow_control_req(dev,
644 /* free all allocated buffers */
645 mei_io_cb_free(cb_pos);
654 * mei_clear_lists - removes all callbacks associated with file
656 * @dev: device structure
657 * @file: file structure
659 * mei_clear_lists is called to clear resources associated with file
660 * when application calls close function or Ctrl-C was pressed
662 * Return: true if callback removed from the list, false otherwise
664 static bool mei_clear_lists(struct mei_device *dev, struct file *file)
666 bool removed = false;
668 /* remove callbacks associated with a file */
669 mei_clear_list(dev, file, &dev->amthif_cmd_list.list);
670 if (mei_clear_list(dev, file, &dev->amthif_rd_complete_list.list))
673 mei_clear_list(dev, file, &dev->ctrl_rd_list.list);
675 if (mei_clear_list(dev, file, &dev->ctrl_wr_list.list))
678 if (mei_clear_list(dev, file, &dev->write_waiting_list.list))
681 if (mei_clear_list(dev, file, &dev->write_list.list))
684 /* check if iamthif_current_cb not NULL */
685 if (dev->iamthif_current_cb && !removed) {
686 /* check file and iamthif current cb association */
687 if (dev->iamthif_current_cb->file_object == file) {
689 mei_io_cb_free(dev->iamthif_current_cb);
690 dev->iamthif_current_cb = NULL;
698 * mei_amthif_release - the release function
700 * @dev: device structure
701 * @file: pointer to file structure
703 * Return: 0 on success, <0 on error
705 int mei_amthif_release(struct mei_device *dev, struct file *file)
707 if (dev->iamthif_open_count > 0)
708 dev->iamthif_open_count--;
710 if (dev->iamthif_file_object == file &&
711 dev->iamthif_state != MEI_IAMTHIF_IDLE) {
713 dev_dbg(dev->dev, "amthif canceled iamthif state %d\n",
715 dev->iamthif_canceled = true;
716 if (dev->iamthif_state == MEI_IAMTHIF_READ_COMPLETE) {
717 dev_dbg(dev->dev, "run next amthif iamthif cb\n");
718 mei_amthif_run_next_cmd(dev);
722 if (mei_clear_lists(dev, file))
723 dev->iamthif_state = MEI_IAMTHIF_IDLE;