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
80 void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr)
83 * no need to check for size as it is guarantied
84 * that length fits into rd_msg_buf
86 mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
87 dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n",
92 * mei_cl_irq_read_msg - process client message
95 * @mei_hdr: header of mei client message
96 * @complete_list: completion list
100 int mei_cl_irq_read_msg(struct mei_cl *cl,
101 struct mei_msg_hdr *mei_hdr,
102 struct mei_cl_cb *complete_list)
104 struct mei_device *dev = cl->dev;
105 struct mei_cl_cb *cb;
106 unsigned char *buffer = NULL;
109 cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list);
111 cl_err(dev, cl, "pending read cb not found\n");
115 if (!mei_cl_is_connected(cl)) {
116 cl_dbg(dev, cl, "not connected\n");
117 cb->status = -ENODEV;
121 if (cb->buf.size == 0 || cb->buf.data == NULL) {
122 cl_err(dev, cl, "response buffer is not allocated.\n");
123 list_move_tail(&cb->list, &complete_list->list);
124 cb->status = -ENOMEM;
128 buf_sz = mei_hdr->length + cb->buf_idx;
129 /* catch for integer overflow */
130 if (buf_sz < cb->buf_idx) {
131 cl_err(dev, cl, "message is too big len %d idx %zu\n",
132 mei_hdr->length, cb->buf_idx);
134 list_move_tail(&cb->list, &complete_list->list);
135 cb->status = -EMSGSIZE;
139 if (cb->buf.size < buf_sz) {
140 cl_dbg(dev, cl, "message overflow. size %zu len %d idx %zu\n",
141 cb->buf.size, mei_hdr->length, cb->buf_idx);
142 buffer = krealloc(cb->buf.data, buf_sz, GFP_KERNEL);
145 cb->status = -ENOMEM;
146 list_move_tail(&cb->list, &complete_list->list);
149 cb->buf.data = buffer;
150 cb->buf.size = buf_sz;
153 buffer = cb->buf.data + cb->buf_idx;
154 mei_read_slots(dev, buffer, mei_hdr->length);
156 cb->buf_idx += mei_hdr->length;
158 if (mei_hdr->msg_complete) {
159 cl_dbg(dev, cl, "completed read length = %zu\n", cb->buf_idx);
160 list_move_tail(&cb->list, &complete_list->list);
162 pm_runtime_mark_last_busy(dev->dev);
163 pm_request_autosuspend(dev->dev);
168 mei_irq_discard_msg(dev, mei_hdr);
174 * mei_cl_irq_disconnect_rsp - send disconnection response message
177 * @cb: callback block.
178 * @cmpl_list: complete list.
180 * Return: 0, OK; otherwise, error.
182 static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
183 struct mei_cl_cb *cmpl_list)
185 struct mei_device *dev = cl->dev;
190 slots = mei_hbuf_empty_slots(dev);
191 msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_response));
193 if (slots < msg_slots)
196 ret = mei_hbm_cl_disconnect_rsp(dev, cl);
197 mei_cl_set_disconnected(cl);
199 mei_me_cl_put(cl->me_cl);
206 * mei_cl_irq_read - processes client read related operation from the
207 * interrupt thread context - request for flow control credits
210 * @cb: callback block.
211 * @cmpl_list: complete list.
213 * Return: 0, OK; otherwise, error.
215 static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
216 struct mei_cl_cb *cmpl_list)
218 struct mei_device *dev = cl->dev;
223 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
224 slots = mei_hbuf_empty_slots(dev);
226 if (slots < msg_slots)
229 ret = mei_hbm_cl_flow_control_req(dev, cl);
233 list_move_tail(&cb->list, &cmpl_list->list);
237 list_move_tail(&cb->list, &cl->rd_pending);
242 static inline bool hdr_is_hbm(struct mei_msg_hdr *mei_hdr)
244 return mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0;
247 static inline bool hdr_is_fixed(struct mei_msg_hdr *mei_hdr)
249 return mei_hdr->host_addr == 0 && mei_hdr->me_addr != 0;
253 * mei_irq_read_handler - bottom half read routine after ISR to
254 * handle the read processing.
256 * @dev: the device structure
257 * @cmpl_list: An instance of our list structure
258 * @slots: slots to read.
260 * Return: 0 on success, <0 on failure.
262 int mei_irq_read_handler(struct mei_device *dev,
263 struct mei_cl_cb *cmpl_list, s32 *slots)
265 struct mei_msg_hdr *mei_hdr;
269 if (!dev->rd_msg_hdr) {
270 dev->rd_msg_hdr = mei_read_hdr(dev);
272 dev_dbg(dev->dev, "slots =%08x.\n", *slots);
274 mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr;
275 dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
277 if (mei_hdr->reserved || !dev->rd_msg_hdr) {
278 dev_err(dev->dev, "corrupted message header 0x%08X\n",
284 if (mei_slots2data(*slots) < mei_hdr->length) {
285 dev_err(dev->dev, "less data available than length=%08x.\n",
287 /* we can't read the message */
293 if (hdr_is_hbm(mei_hdr)) {
294 ret = mei_hbm_dispatch(dev, mei_hdr);
296 dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n",
303 /* find recipient cl */
304 list_for_each_entry(cl, &dev->file_list, link) {
305 if (mei_cl_hbm_equal(cl, mei_hdr)) {
306 cl_dbg(dev, cl, "got a message\n");
311 /* if no recipient cl was found we assume corrupted header */
312 if (&cl->link == &dev->file_list) {
313 /* A message for not connected fixed address clients
314 * should be silently discarded
316 if (hdr_is_fixed(mei_hdr)) {
317 mei_irq_discard_msg(dev, mei_hdr);
321 dev_err(dev->dev, "no destination client found 0x%08X\n",
327 if (cl == &dev->iamthif_cl) {
328 ret = mei_amthif_irq_read_msg(cl, mei_hdr, cmpl_list);
330 ret = mei_cl_irq_read_msg(cl, mei_hdr, cmpl_list);
335 /* reset the number of slots and header */
336 *slots = mei_count_full_read_slots(dev);
339 if (*slots == -EOVERFLOW) {
340 /* overflow - reset */
341 dev_err(dev->dev, "resetting due to slots overflow.\n");
342 /* set the event since message has been read */
349 EXPORT_SYMBOL_GPL(mei_irq_read_handler);
353 * mei_irq_write_handler - dispatch write requests
356 * @dev: the device structure
357 * @cmpl_list: An instance of our list structure
359 * Return: 0 on success, <0 on failure.
361 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
365 struct mei_cl_cb *cb, *next;
366 struct mei_cl_cb *list;
371 if (!mei_hbuf_acquire(dev))
374 slots = mei_hbuf_empty_slots(dev);
378 /* complete all waiting for write CB */
379 dev_dbg(dev->dev, "complete all waiting for write cb.\n");
381 list = &dev->write_waiting_list;
382 list_for_each_entry_safe(cb, next, &list->list, list) {
386 cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
387 cl->writing_state = MEI_WRITE_COMPLETE;
388 list_move_tail(&cb->list, &cmpl_list->list);
391 /* complete control write list CB */
392 dev_dbg(dev->dev, "complete control write list cb.\n");
393 list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list.list, list) {
395 switch (cb->fop_type) {
396 case MEI_FOP_DISCONNECT:
397 /* send disconnect message */
398 ret = mei_cl_irq_disconnect(cl, cb, cmpl_list);
404 /* send flow control message */
405 ret = mei_cl_irq_read(cl, cb, cmpl_list);
410 case MEI_FOP_CONNECT:
411 /* connect message */
412 ret = mei_cl_irq_connect(cl, cb, cmpl_list);
417 case MEI_FOP_DISCONNECT_RSP:
418 /* send disconnect resp */
419 ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
424 case MEI_FOP_NOTIFY_START:
425 case MEI_FOP_NOTIFY_STOP:
426 ret = mei_cl_irq_notify(cl, cb, cmpl_list);
435 /* complete write list CB */
436 dev_dbg(dev->dev, "complete write list cb.\n");
437 list_for_each_entry_safe(cb, next, &dev->write_list.list, list) {
439 if (cl == &dev->iamthif_cl)
440 ret = mei_amthif_irq_write(cl, cb, cmpl_list);
442 ret = mei_cl_irq_write(cl, cb, cmpl_list);
448 EXPORT_SYMBOL_GPL(mei_irq_write_handler);
452 * mei_connect_timeout - connect/disconnect timeouts
456 static void mei_connect_timeout(struct mei_cl *cl)
458 struct mei_device *dev = cl->dev;
460 if (cl->state == MEI_FILE_CONNECTING) {
461 if (dev->hbm_f_dot_supported) {
462 cl->state = MEI_FILE_DISCONNECT_REQUIRED;
471 * mei_timer - timer function.
473 * @work: pointer to the work_struct structure
476 void mei_timer(struct work_struct *work)
480 struct mei_device *dev = container_of(work,
481 struct mei_device, timer_work.work);
484 mutex_lock(&dev->device_lock);
486 /* Catch interrupt stalls during HBM init handshake */
487 if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
488 dev->hbm_state != MEI_HBM_IDLE) {
490 if (dev->init_clients_timer) {
491 if (--dev->init_clients_timer == 0) {
492 dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n",
500 if (dev->dev_state != MEI_DEV_ENABLED)
503 /*** connect/disconnect timeouts ***/
504 list_for_each_entry(cl, &dev->file_list, link) {
505 if (cl->timer_count) {
506 if (--cl->timer_count == 0) {
507 dev_err(dev->dev, "timer: connect/disconnect timeout.\n");
508 mei_connect_timeout(cl);
514 if (!mei_cl_is_connected(&dev->iamthif_cl))
517 if (dev->iamthif_stall_timer) {
518 if (--dev->iamthif_stall_timer == 0) {
519 dev_err(dev->dev, "timer: amthif hanged.\n");
521 dev->iamthif_canceled = false;
522 dev->iamthif_state = MEI_IAMTHIF_IDLE;
524 mei_io_cb_free(dev->iamthif_current_cb);
525 dev->iamthif_current_cb = NULL;
527 dev->iamthif_fp = NULL;
528 mei_amthif_run_next_cmd(dev);
533 if (dev->dev_state != MEI_DEV_DISABLED)
534 schedule_delayed_work(&dev->timer_work, 2 * HZ);
535 mutex_unlock(&dev->device_lock);