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>
24 #include <linux/pm_runtime.h>
26 #include <linux/mei.h>
34 * mei_irq_compl_handler - dispatch complete handlers
35 * for the completed callbacks
38 * @compl_list: list of completed cbs
40 void mei_irq_compl_handler(struct mei_device *dev, struct mei_cl_cb *compl_list)
42 struct mei_cl_cb *cb, *next;
45 list_for_each_entry_safe(cb, next, &compl_list->list, list) {
47 list_del_init(&cb->list);
49 dev_dbg(dev->dev, "completing call back.\n");
50 if (cl == &dev->iamthif_cl)
51 mei_amthif_complete(cl, cb);
53 mei_cl_complete(cl, cb);
56 EXPORT_SYMBOL_GPL(mei_irq_compl_handler);
59 * mei_cl_hbm_equal - check if hbm is addressed to the client
62 * @mei_hdr: header of mei client message
64 * Return: true if matches, false otherwise
66 static inline int mei_cl_hbm_equal(struct mei_cl *cl,
67 struct mei_msg_hdr *mei_hdr)
69 return mei_cl_host_addr(cl) == mei_hdr->host_addr &&
70 mei_cl_me_id(cl) == mei_hdr->me_addr;
74 * mei_irq_discard_msg - discard received message
77 * @hdr: message header
79 void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr)
82 * no need to check for size as it is guarantied
83 * that length fits into rd_msg_buf
85 mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
86 dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n",
91 * mei_cl_irq_read_msg - process client message
94 * @mei_hdr: header of mei client message
95 * @complete_list: completion list
99 int mei_cl_irq_read_msg(struct mei_cl *cl,
100 struct mei_msg_hdr *mei_hdr,
101 struct mei_cl_cb *complete_list)
103 struct mei_device *dev = cl->dev;
104 struct mei_cl_cb *cb;
107 cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list);
109 if (!mei_cl_is_fixed_address(cl)) {
110 cl_err(dev, cl, "pending read cb not found\n");
113 cb = mei_cl_alloc_cb(cl, mei_cl_mtu(cl), MEI_FOP_READ, cl->fp);
116 list_add_tail(&cb->list, &cl->rd_pending);
119 if (!mei_cl_is_connected(cl)) {
120 cl_dbg(dev, cl, "not connected\n");
121 list_move_tail(&cb->list, &complete_list->list);
122 cb->status = -ENODEV;
126 buf_sz = mei_hdr->length + cb->buf_idx;
127 /* catch for integer overflow */
128 if (buf_sz < cb->buf_idx) {
129 cl_err(dev, cl, "message is too big len %d idx %zu\n",
130 mei_hdr->length, cb->buf_idx);
132 list_move_tail(&cb->list, &complete_list->list);
133 cb->status = -EMSGSIZE;
137 if (cb->buf.size < buf_sz) {
138 cl_dbg(dev, cl, "message overflow. size %zu len %d idx %zu\n",
139 cb->buf.size, mei_hdr->length, cb->buf_idx);
141 list_move_tail(&cb->list, &complete_list->list);
142 cb->status = -EMSGSIZE;
146 mei_read_slots(dev, cb->buf.data + cb->buf_idx, mei_hdr->length);
148 cb->buf_idx += mei_hdr->length;
150 if (mei_hdr->msg_complete) {
151 cl_dbg(dev, cl, "completed read length = %zu\n", cb->buf_idx);
152 list_move_tail(&cb->list, &complete_list->list);
154 pm_runtime_mark_last_busy(dev->dev);
155 pm_request_autosuspend(dev->dev);
161 mei_irq_discard_msg(dev, mei_hdr);
166 * mei_cl_irq_disconnect_rsp - send disconnection response message
169 * @cb: callback block.
170 * @cmpl_list: complete list.
172 * Return: 0, OK; otherwise, error.
174 static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
175 struct mei_cl_cb *cmpl_list)
177 struct mei_device *dev = cl->dev;
182 slots = mei_hbuf_empty_slots(dev);
183 msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_response));
185 if (slots < msg_slots)
188 ret = mei_hbm_cl_disconnect_rsp(dev, cl);
189 list_move_tail(&cb->list, &cmpl_list->list);
195 * mei_cl_irq_read - processes client read related operation from the
196 * interrupt thread context - request for flow control credits
199 * @cb: callback block.
200 * @cmpl_list: complete list.
202 * Return: 0, OK; otherwise, error.
204 static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
205 struct mei_cl_cb *cmpl_list)
207 struct mei_device *dev = cl->dev;
212 if (!list_empty(&cl->rd_pending))
215 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
216 slots = mei_hbuf_empty_slots(dev);
218 if (slots < msg_slots)
221 ret = mei_hbm_cl_flow_control_req(dev, cl);
225 list_move_tail(&cb->list, &cmpl_list->list);
229 pm_runtime_mark_last_busy(dev->dev);
230 pm_request_autosuspend(dev->dev);
232 list_move_tail(&cb->list, &cl->rd_pending);
237 static inline bool hdr_is_hbm(struct mei_msg_hdr *mei_hdr)
239 return mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0;
242 static inline bool hdr_is_fixed(struct mei_msg_hdr *mei_hdr)
244 return mei_hdr->host_addr == 0 && mei_hdr->me_addr != 0;
248 * mei_irq_read_handler - bottom half read routine after ISR to
249 * handle the read processing.
251 * @dev: the device structure
252 * @cmpl_list: An instance of our list structure
253 * @slots: slots to read.
255 * Return: 0 on success, <0 on failure.
257 int mei_irq_read_handler(struct mei_device *dev,
258 struct mei_cl_cb *cmpl_list, s32 *slots)
260 struct mei_msg_hdr *mei_hdr;
264 if (!dev->rd_msg_hdr) {
265 dev->rd_msg_hdr = mei_read_hdr(dev);
267 dev_dbg(dev->dev, "slots =%08x.\n", *slots);
269 mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr;
270 dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
272 if (mei_hdr->reserved || !dev->rd_msg_hdr) {
273 dev_err(dev->dev, "corrupted message header 0x%08X\n",
279 if (mei_slots2data(*slots) < mei_hdr->length) {
280 dev_err(dev->dev, "less data available than length=%08x.\n",
282 /* we can't read the message */
288 if (hdr_is_hbm(mei_hdr)) {
289 ret = mei_hbm_dispatch(dev, mei_hdr);
291 dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n",
298 /* find recipient cl */
299 list_for_each_entry(cl, &dev->file_list, link) {
300 if (mei_cl_hbm_equal(cl, mei_hdr)) {
301 cl_dbg(dev, cl, "got a message\n");
306 /* if no recipient cl was found we assume corrupted header */
307 if (&cl->link == &dev->file_list) {
308 /* A message for not connected fixed address clients
309 * should be silently discarded
311 if (hdr_is_fixed(mei_hdr)) {
312 mei_irq_discard_msg(dev, mei_hdr);
316 dev_err(dev->dev, "no destination client found 0x%08X\n",
322 if (cl == &dev->iamthif_cl) {
323 ret = mei_amthif_irq_read_msg(cl, mei_hdr, cmpl_list);
325 ret = mei_cl_irq_read_msg(cl, mei_hdr, cmpl_list);
330 /* reset the number of slots and header */
331 *slots = mei_count_full_read_slots(dev);
334 if (*slots == -EOVERFLOW) {
335 /* overflow - reset */
336 dev_err(dev->dev, "resetting due to slots overflow.\n");
337 /* set the event since message has been read */
344 EXPORT_SYMBOL_GPL(mei_irq_read_handler);
348 * mei_irq_write_handler - dispatch write requests
351 * @dev: the device structure
352 * @cmpl_list: An instance of our list structure
354 * Return: 0 on success, <0 on failure.
356 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
360 struct mei_cl_cb *cb, *next;
361 struct mei_cl_cb *list;
366 if (!mei_hbuf_acquire(dev))
369 slots = mei_hbuf_empty_slots(dev);
373 /* complete all waiting for write CB */
374 dev_dbg(dev->dev, "complete all waiting for write cb.\n");
376 list = &dev->write_waiting_list;
377 list_for_each_entry_safe(cb, next, &list->list, list) {
381 cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
382 cl->writing_state = MEI_WRITE_COMPLETE;
383 list_move_tail(&cb->list, &cmpl_list->list);
386 /* complete control write list CB */
387 dev_dbg(dev->dev, "complete control write list cb.\n");
388 list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list.list, list) {
390 switch (cb->fop_type) {
391 case MEI_FOP_DISCONNECT:
392 /* send disconnect message */
393 ret = mei_cl_irq_disconnect(cl, cb, cmpl_list);
399 /* send flow control message */
400 ret = mei_cl_irq_read(cl, cb, cmpl_list);
405 case MEI_FOP_CONNECT:
406 /* connect message */
407 ret = mei_cl_irq_connect(cl, cb, cmpl_list);
412 case MEI_FOP_DISCONNECT_RSP:
413 /* send disconnect resp */
414 ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
419 case MEI_FOP_NOTIFY_START:
420 case MEI_FOP_NOTIFY_STOP:
421 ret = mei_cl_irq_notify(cl, cb, cmpl_list);
430 /* complete write list CB */
431 dev_dbg(dev->dev, "complete write list cb.\n");
432 list_for_each_entry_safe(cb, next, &dev->write_list.list, list) {
434 if (cl == &dev->iamthif_cl)
435 ret = mei_amthif_irq_write(cl, cb, cmpl_list);
437 ret = mei_cl_irq_write(cl, cb, cmpl_list);
443 EXPORT_SYMBOL_GPL(mei_irq_write_handler);
447 * mei_connect_timeout - connect/disconnect timeouts
451 static void mei_connect_timeout(struct mei_cl *cl)
453 struct mei_device *dev = cl->dev;
455 if (cl->state == MEI_FILE_CONNECTING) {
456 if (dev->hbm_f_dot_supported) {
457 cl->state = MEI_FILE_DISCONNECT_REQUIRED;
465 #define MEI_STALL_TIMER_FREQ (2 * HZ)
467 * mei_schedule_stall_timer - re-arm stall_timer work
469 * Schedule stall timer
471 * @dev: the device structure
473 void mei_schedule_stall_timer(struct mei_device *dev)
475 schedule_delayed_work(&dev->timer_work, MEI_STALL_TIMER_FREQ);
479 * mei_timer - timer function.
481 * @work: pointer to the work_struct structure
484 void mei_timer(struct work_struct *work)
487 struct mei_device *dev = container_of(work,
488 struct mei_device, timer_work.work);
489 bool reschedule_timer = false;
491 mutex_lock(&dev->device_lock);
493 /* Catch interrupt stalls during HBM init handshake */
494 if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
495 dev->hbm_state != MEI_HBM_IDLE) {
497 if (dev->init_clients_timer) {
498 if (--dev->init_clients_timer == 0) {
499 dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n",
504 reschedule_timer = true;
508 if (dev->dev_state != MEI_DEV_ENABLED)
511 /*** connect/disconnect timeouts ***/
512 list_for_each_entry(cl, &dev->file_list, link) {
513 if (cl->timer_count) {
514 if (--cl->timer_count == 0) {
515 dev_err(dev->dev, "timer: connect/disconnect timeout.\n");
516 mei_connect_timeout(cl);
519 reschedule_timer = true;
523 if (!mei_cl_is_connected(&dev->iamthif_cl))
526 if (dev->iamthif_stall_timer) {
527 if (--dev->iamthif_stall_timer == 0) {
528 dev_err(dev->dev, "timer: amthif hanged.\n");
531 mei_amthif_run_next_cmd(dev);
534 reschedule_timer = true;
538 if (dev->dev_state != MEI_DEV_DISABLED && reschedule_timer)
539 mei_schedule_stall_timer(dev);
541 mutex_unlock(&dev->device_lock);