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;
105 unsigned char *buffer = NULL;
108 cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list);
110 cl_err(dev, cl, "pending read cb not found\n");
114 if (!mei_cl_is_connected(cl)) {
115 cl_dbg(dev, cl, "not connected\n");
116 cb->status = -ENODEV;
120 if (cb->buf.size == 0 || cb->buf.data == NULL) {
121 cl_err(dev, cl, "response buffer is not allocated.\n");
122 list_move_tail(&cb->list, &complete_list->list);
123 cb->status = -ENOMEM;
127 buf_sz = mei_hdr->length + cb->buf_idx;
128 /* catch for integer overflow */
129 if (buf_sz < cb->buf_idx) {
130 cl_err(dev, cl, "message is too big len %d idx %zu\n",
131 mei_hdr->length, cb->buf_idx);
133 list_move_tail(&cb->list, &complete_list->list);
134 cb->status = -EMSGSIZE;
138 if (cb->buf.size < buf_sz) {
139 cl_dbg(dev, cl, "message overflow. size %zu len %d idx %zu\n",
140 cb->buf.size, mei_hdr->length, cb->buf_idx);
141 buffer = krealloc(cb->buf.data, buf_sz, GFP_KERNEL);
144 cb->status = -ENOMEM;
145 list_move_tail(&cb->list, &complete_list->list);
148 cb->buf.data = buffer;
149 cb->buf.size = buf_sz;
152 buffer = cb->buf.data + cb->buf_idx;
153 mei_read_slots(dev, buffer, mei_hdr->length);
155 cb->buf_idx += mei_hdr->length;
157 if (mei_hdr->msg_complete) {
158 cl_dbg(dev, cl, "completed read length = %zu\n", cb->buf_idx);
159 list_move_tail(&cb->list, &complete_list->list);
161 pm_runtime_mark_last_busy(dev->dev);
162 pm_request_autosuspend(dev->dev);
167 mei_irq_discard_msg(dev, mei_hdr);
173 * mei_cl_irq_disconnect_rsp - send disconnection response message
176 * @cb: callback block.
177 * @cmpl_list: complete list.
179 * Return: 0, OK; otherwise, error.
181 static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
182 struct mei_cl_cb *cmpl_list)
184 struct mei_device *dev = cl->dev;
189 slots = mei_hbuf_empty_slots(dev);
190 msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_response));
192 if (slots < msg_slots)
195 ret = mei_hbm_cl_disconnect_rsp(dev, cl);
196 list_move_tail(&cb->list, &cmpl_list->list);
202 * mei_cl_irq_read - processes client read related operation from the
203 * interrupt thread context - request for flow control credits
206 * @cb: callback block.
207 * @cmpl_list: complete list.
209 * Return: 0, OK; otherwise, error.
211 static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
212 struct mei_cl_cb *cmpl_list)
214 struct mei_device *dev = cl->dev;
219 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
220 slots = mei_hbuf_empty_slots(dev);
222 if (slots < msg_slots)
225 ret = mei_hbm_cl_flow_control_req(dev, cl);
229 list_move_tail(&cb->list, &cmpl_list->list);
233 list_move_tail(&cb->list, &cl->rd_pending);
238 static inline bool hdr_is_hbm(struct mei_msg_hdr *mei_hdr)
240 return mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0;
243 static inline bool hdr_is_fixed(struct mei_msg_hdr *mei_hdr)
245 return mei_hdr->host_addr == 0 && mei_hdr->me_addr != 0;
249 * mei_irq_read_handler - bottom half read routine after ISR to
250 * handle the read processing.
252 * @dev: the device structure
253 * @cmpl_list: An instance of our list structure
254 * @slots: slots to read.
256 * Return: 0 on success, <0 on failure.
258 int mei_irq_read_handler(struct mei_device *dev,
259 struct mei_cl_cb *cmpl_list, s32 *slots)
261 struct mei_msg_hdr *mei_hdr;
265 if (!dev->rd_msg_hdr) {
266 dev->rd_msg_hdr = mei_read_hdr(dev);
268 dev_dbg(dev->dev, "slots =%08x.\n", *slots);
270 mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr;
271 dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
273 if (mei_hdr->reserved || !dev->rd_msg_hdr) {
274 dev_err(dev->dev, "corrupted message header 0x%08X\n",
280 if (mei_slots2data(*slots) < mei_hdr->length) {
281 dev_err(dev->dev, "less data available than length=%08x.\n",
283 /* we can't read the message */
289 if (hdr_is_hbm(mei_hdr)) {
290 ret = mei_hbm_dispatch(dev, mei_hdr);
292 dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n",
299 /* find recipient cl */
300 list_for_each_entry(cl, &dev->file_list, link) {
301 if (mei_cl_hbm_equal(cl, mei_hdr)) {
302 cl_dbg(dev, cl, "got a message\n");
307 /* if no recipient cl was found we assume corrupted header */
308 if (&cl->link == &dev->file_list) {
309 /* A message for not connected fixed address clients
310 * should be silently discarded
312 if (hdr_is_fixed(mei_hdr)) {
313 mei_irq_discard_msg(dev, mei_hdr);
317 dev_err(dev->dev, "no destination client found 0x%08X\n",
323 if (cl == &dev->iamthif_cl) {
324 ret = mei_amthif_irq_read_msg(cl, mei_hdr, cmpl_list);
326 ret = mei_cl_irq_read_msg(cl, mei_hdr, cmpl_list);
331 /* reset the number of slots and header */
332 *slots = mei_count_full_read_slots(dev);
335 if (*slots == -EOVERFLOW) {
336 /* overflow - reset */
337 dev_err(dev->dev, "resetting due to slots overflow.\n");
338 /* set the event since message has been read */
345 EXPORT_SYMBOL_GPL(mei_irq_read_handler);
349 * mei_irq_write_handler - dispatch write requests
352 * @dev: the device structure
353 * @cmpl_list: An instance of our list structure
355 * Return: 0 on success, <0 on failure.
357 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
361 struct mei_cl_cb *cb, *next;
362 struct mei_cl_cb *list;
367 if (!mei_hbuf_acquire(dev))
370 slots = mei_hbuf_empty_slots(dev);
374 /* complete all waiting for write CB */
375 dev_dbg(dev->dev, "complete all waiting for write cb.\n");
377 list = &dev->write_waiting_list;
378 list_for_each_entry_safe(cb, next, &list->list, list) {
382 cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
383 cl->writing_state = MEI_WRITE_COMPLETE;
384 list_move_tail(&cb->list, &cmpl_list->list);
387 /* complete control write list CB */
388 dev_dbg(dev->dev, "complete control write list cb.\n");
389 list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list.list, list) {
391 switch (cb->fop_type) {
392 case MEI_FOP_DISCONNECT:
393 /* send disconnect message */
394 ret = mei_cl_irq_disconnect(cl, cb, cmpl_list);
400 /* send flow control message */
401 ret = mei_cl_irq_read(cl, cb, cmpl_list);
406 case MEI_FOP_CONNECT:
407 /* connect message */
408 ret = mei_cl_irq_connect(cl, cb, cmpl_list);
413 case MEI_FOP_DISCONNECT_RSP:
414 /* send disconnect resp */
415 ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
420 case MEI_FOP_NOTIFY_START:
421 case MEI_FOP_NOTIFY_STOP:
422 ret = mei_cl_irq_notify(cl, cb, cmpl_list);
431 /* complete write list CB */
432 dev_dbg(dev->dev, "complete write list cb.\n");
433 list_for_each_entry_safe(cb, next, &dev->write_list.list, list) {
435 if (cl == &dev->iamthif_cl)
436 ret = mei_amthif_irq_write(cl, cb, cmpl_list);
438 ret = mei_cl_irq_write(cl, cb, cmpl_list);
444 EXPORT_SYMBOL_GPL(mei_irq_write_handler);
448 * mei_connect_timeout - connect/disconnect timeouts
452 static void mei_connect_timeout(struct mei_cl *cl)
454 struct mei_device *dev = cl->dev;
456 if (cl->state == MEI_FILE_CONNECTING) {
457 if (dev->hbm_f_dot_supported) {
458 cl->state = MEI_FILE_DISCONNECT_REQUIRED;
467 * mei_timer - timer function.
469 * @work: pointer to the work_struct structure
472 void mei_timer(struct work_struct *work)
476 struct mei_device *dev = container_of(work,
477 struct mei_device, timer_work.work);
480 mutex_lock(&dev->device_lock);
482 /* Catch interrupt stalls during HBM init handshake */
483 if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
484 dev->hbm_state != MEI_HBM_IDLE) {
486 if (dev->init_clients_timer) {
487 if (--dev->init_clients_timer == 0) {
488 dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n",
496 if (dev->dev_state != MEI_DEV_ENABLED)
499 /*** connect/disconnect timeouts ***/
500 list_for_each_entry(cl, &dev->file_list, link) {
501 if (cl->timer_count) {
502 if (--cl->timer_count == 0) {
503 dev_err(dev->dev, "timer: connect/disconnect timeout.\n");
504 mei_connect_timeout(cl);
510 if (!mei_cl_is_connected(&dev->iamthif_cl))
513 if (dev->iamthif_stall_timer) {
514 if (--dev->iamthif_stall_timer == 0) {
515 dev_err(dev->dev, "timer: amthif hanged.\n");
517 dev->iamthif_canceled = false;
518 dev->iamthif_state = MEI_IAMTHIF_IDLE;
520 mei_io_cb_free(dev->iamthif_current_cb);
521 dev->iamthif_current_cb = NULL;
523 dev->iamthif_fp = NULL;
524 mei_amthif_run_next_cmd(dev);
529 if (dev->dev_state != MEI_DEV_DISABLED)
530 schedule_delayed_work(&dev->timer_work, 2 * HZ);
531 mutex_unlock(&dev->device_lock);