xref: /linux/drivers/misc/mei/hbm.c (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
1 /*
2  *
3  * Intel Management Engine Interface (Intel MEI) Linux driver
4  * Copyright (c) 2003-2012, Intel Corporation.
5  *
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.
9  *
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
13  * more details.
14  *
15  */
16 
17 #include <linux/export.h>
18 #include <linux/sched.h>
19 #include <linux/wait.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/slab.h>
22 
23 #include <linux/mei.h>
24 
25 #include "mei_dev.h"
26 #include "hbm.h"
27 #include "client.h"
28 
29 static const char *mei_hbm_status_str(enum mei_hbm_status status)
30 {
31 #define MEI_HBM_STATUS(status) case MEI_HBMS_##status: return #status
32 	switch (status) {
33 	MEI_HBM_STATUS(SUCCESS);
34 	MEI_HBM_STATUS(CLIENT_NOT_FOUND);
35 	MEI_HBM_STATUS(ALREADY_EXISTS);
36 	MEI_HBM_STATUS(REJECTED);
37 	MEI_HBM_STATUS(INVALID_PARAMETER);
38 	MEI_HBM_STATUS(NOT_ALLOWED);
39 	MEI_HBM_STATUS(ALREADY_STARTED);
40 	MEI_HBM_STATUS(NOT_STARTED);
41 	default: return "unknown";
42 	}
43 #undef MEI_HBM_STATUS
44 };
45 
46 static const char *mei_cl_conn_status_str(enum mei_cl_connect_status status)
47 {
48 #define MEI_CL_CS(status) case MEI_CL_CONN_##status: return #status
49 	switch (status) {
50 	MEI_CL_CS(SUCCESS);
51 	MEI_CL_CS(NOT_FOUND);
52 	MEI_CL_CS(ALREADY_STARTED);
53 	MEI_CL_CS(OUT_OF_RESOURCES);
54 	MEI_CL_CS(MESSAGE_SMALL);
55 	MEI_CL_CS(NOT_ALLOWED);
56 	default: return "unknown";
57 	}
58 #undef MEI_CL_CCS
59 }
60 
61 const char *mei_hbm_state_str(enum mei_hbm_state state)
62 {
63 #define MEI_HBM_STATE(state) case MEI_HBM_##state: return #state
64 	switch (state) {
65 	MEI_HBM_STATE(IDLE);
66 	MEI_HBM_STATE(STARTING);
67 	MEI_HBM_STATE(STARTED);
68 	MEI_HBM_STATE(ENUM_CLIENTS);
69 	MEI_HBM_STATE(CLIENT_PROPERTIES);
70 	MEI_HBM_STATE(STOPPED);
71 	default:
72 		return "unknown";
73 	}
74 #undef MEI_HBM_STATE
75 }
76 
77 /**
78  * mei_cl_conn_status_to_errno - convert client connect response
79  * status to error code
80  *
81  * @status: client connect response status
82  *
83  * Return: corresponding error code
84  */
85 static int mei_cl_conn_status_to_errno(enum mei_cl_connect_status status)
86 {
87 	switch (status) {
88 	case MEI_CL_CONN_SUCCESS:          return 0;
89 	case MEI_CL_CONN_NOT_FOUND:        return -ENOTTY;
90 	case MEI_CL_CONN_ALREADY_STARTED:  return -EBUSY;
91 	case MEI_CL_CONN_OUT_OF_RESOURCES: return -EBUSY;
92 	case MEI_CL_CONN_MESSAGE_SMALL:    return -EINVAL;
93 	case MEI_CL_CONN_NOT_ALLOWED:      return -EBUSY;
94 	default:                           return -EINVAL;
95 	}
96 }
97 
98 /**
99  * mei_hbm_idle - set hbm to idle state
100  *
101  * @dev: the device structure
102  */
103 void mei_hbm_idle(struct mei_device *dev)
104 {
105 	dev->init_clients_timer = 0;
106 	dev->hbm_state = MEI_HBM_IDLE;
107 }
108 
109 /**
110  * mei_hbm_reset - reset hbm counters and book keeping data structurs
111  *
112  * @dev: the device structure
113  */
114 void mei_hbm_reset(struct mei_device *dev)
115 {
116 	mei_me_cl_rm_all(dev);
117 
118 	mei_hbm_idle(dev);
119 }
120 
121 /**
122  * mei_hbm_hdr - construct hbm header
123  *
124  * @hdr: hbm header
125  * @length: payload length
126  */
127 
128 static inline void mei_hbm_hdr(struct mei_msg_hdr *hdr, size_t length)
129 {
130 	hdr->host_addr = 0;
131 	hdr->me_addr = 0;
132 	hdr->length = length;
133 	hdr->msg_complete = 1;
134 	hdr->reserved = 0;
135 	hdr->internal = 0;
136 }
137 
138 /**
139  * mei_hbm_cl_hdr - construct client hbm header
140  *
141  * @cl: client
142  * @hbm_cmd: host bus message command
143  * @buf: buffer for cl header
144  * @len: buffer length
145  */
146 static inline
147 void mei_hbm_cl_hdr(struct mei_cl *cl, u8 hbm_cmd, void *buf, size_t len)
148 {
149 	struct mei_hbm_cl_cmd *cmd = buf;
150 
151 	memset(cmd, 0, len);
152 
153 	cmd->hbm_cmd = hbm_cmd;
154 	cmd->host_addr = mei_cl_host_addr(cl);
155 	cmd->me_addr = mei_cl_me_id(cl);
156 }
157 
158 /**
159  * mei_hbm_cl_write - write simple hbm client message
160  *
161  * @dev: the device structure
162  * @cl: client
163  * @hbm_cmd: host bus message command
164  * @buf: message buffer
165  * @len: buffer length
166  *
167  * Return: 0 on success, <0 on failure.
168  */
169 static inline int mei_hbm_cl_write(struct mei_device *dev, struct mei_cl *cl,
170 				   u8 hbm_cmd, void *buf, size_t len)
171 {
172 	struct mei_msg_hdr mei_hdr;
173 
174 	mei_hbm_hdr(&mei_hdr, len);
175 	mei_hbm_cl_hdr(cl, hbm_cmd, buf, len);
176 
177 	return mei_write_message(dev, &mei_hdr, buf);
178 }
179 
180 /**
181  * mei_hbm_cl_addr_equal - check if the client's and
182  *	the message address match
183  *
184  * @cl: client
185  * @cmd: hbm client message
186  *
187  * Return: true if addresses are the same
188  */
189 static inline
190 bool mei_hbm_cl_addr_equal(struct mei_cl *cl, struct mei_hbm_cl_cmd *cmd)
191 {
192 	return  mei_cl_host_addr(cl) == cmd->host_addr &&
193 		mei_cl_me_id(cl) == cmd->me_addr;
194 }
195 
196 /**
197  * mei_hbm_cl_find_by_cmd - find recipient client
198  *
199  * @dev: the device structure
200  * @buf: a buffer with hbm cl command
201  *
202  * Return: the recipient client or NULL if not found
203  */
204 static inline
205 struct mei_cl *mei_hbm_cl_find_by_cmd(struct mei_device *dev, void *buf)
206 {
207 	struct mei_hbm_cl_cmd *cmd = (struct mei_hbm_cl_cmd *)buf;
208 	struct mei_cl *cl;
209 
210 	list_for_each_entry(cl, &dev->file_list, link)
211 		if (mei_hbm_cl_addr_equal(cl, cmd))
212 			return cl;
213 	return NULL;
214 }
215 
216 
217 /**
218  * mei_hbm_start_wait - wait for start response message.
219  *
220  * @dev: the device structure
221  *
222  * Return: 0 on success and < 0 on failure
223  */
224 int mei_hbm_start_wait(struct mei_device *dev)
225 {
226 	int ret;
227 
228 	if (dev->hbm_state > MEI_HBM_STARTING)
229 		return 0;
230 
231 	mutex_unlock(&dev->device_lock);
232 	ret = wait_event_timeout(dev->wait_hbm_start,
233 			dev->hbm_state != MEI_HBM_STARTING,
234 			mei_secs_to_jiffies(MEI_HBM_TIMEOUT));
235 	mutex_lock(&dev->device_lock);
236 
237 	if (ret == 0 && (dev->hbm_state <= MEI_HBM_STARTING)) {
238 		dev->hbm_state = MEI_HBM_IDLE;
239 		dev_err(dev->dev, "waiting for mei start failed\n");
240 		return -ETIME;
241 	}
242 	return 0;
243 }
244 
245 /**
246  * mei_hbm_start_req - sends start request message.
247  *
248  * @dev: the device structure
249  *
250  * Return: 0 on success and < 0 on failure
251  */
252 int mei_hbm_start_req(struct mei_device *dev)
253 {
254 	struct mei_msg_hdr mei_hdr;
255 	struct hbm_host_version_request start_req;
256 	const size_t len = sizeof(struct hbm_host_version_request);
257 	int ret;
258 
259 	mei_hbm_reset(dev);
260 
261 	mei_hbm_hdr(&mei_hdr, len);
262 
263 	/* host start message */
264 	memset(&start_req, 0, len);
265 	start_req.hbm_cmd = HOST_START_REQ_CMD;
266 	start_req.host_version.major_version = HBM_MAJOR_VERSION;
267 	start_req.host_version.minor_version = HBM_MINOR_VERSION;
268 
269 	dev->hbm_state = MEI_HBM_IDLE;
270 	ret = mei_write_message(dev, &mei_hdr, &start_req);
271 	if (ret) {
272 		dev_err(dev->dev, "version message write failed: ret = %d\n",
273 			ret);
274 		return ret;
275 	}
276 
277 	dev->hbm_state = MEI_HBM_STARTING;
278 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
279 	mei_schedule_stall_timer(dev);
280 	return 0;
281 }
282 
283 /**
284  * mei_hbm_enum_clients_req - sends enumeration client request message.
285  *
286  * @dev: the device structure
287  *
288  * Return: 0 on success and < 0 on failure
289  */
290 static int mei_hbm_enum_clients_req(struct mei_device *dev)
291 {
292 	struct mei_msg_hdr mei_hdr;
293 	struct hbm_host_enum_request enum_req;
294 	const size_t len = sizeof(struct hbm_host_enum_request);
295 	int ret;
296 
297 	/* enumerate clients */
298 	mei_hbm_hdr(&mei_hdr, len);
299 
300 	memset(&enum_req, 0, len);
301 	enum_req.hbm_cmd = HOST_ENUM_REQ_CMD;
302 	enum_req.flags |= dev->hbm_f_dc_supported ?
303 			  MEI_HBM_ENUM_F_ALLOW_ADD : 0;
304 	enum_req.flags |= dev->hbm_f_ie_supported ?
305 			  MEI_HBM_ENUM_F_IMMEDIATE_ENUM : 0;
306 
307 	ret = mei_write_message(dev, &mei_hdr, &enum_req);
308 	if (ret) {
309 		dev_err(dev->dev, "enumeration request write failed: ret = %d.\n",
310 			ret);
311 		return ret;
312 	}
313 	dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
314 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
315 	mei_schedule_stall_timer(dev);
316 	return 0;
317 }
318 
319 /**
320  * mei_hbm_me_cl_add - add new me client to the list
321  *
322  * @dev: the device structure
323  * @res: hbm property response
324  *
325  * Return: 0 on success and -ENOMEM on allocation failure
326  */
327 
328 static int mei_hbm_me_cl_add(struct mei_device *dev,
329 			     struct hbm_props_response *res)
330 {
331 	struct mei_me_client *me_cl;
332 	const uuid_le *uuid = &res->client_properties.protocol_name;
333 
334 	mei_me_cl_rm_by_uuid(dev, uuid);
335 
336 	me_cl = kzalloc(sizeof(struct mei_me_client), GFP_KERNEL);
337 	if (!me_cl)
338 		return -ENOMEM;
339 
340 	mei_me_cl_init(me_cl);
341 
342 	me_cl->props = res->client_properties;
343 	me_cl->client_id = res->me_addr;
344 	me_cl->tx_flow_ctrl_creds = 0;
345 
346 	mei_me_cl_add(dev, me_cl);
347 
348 	return 0;
349 }
350 
351 /**
352  * mei_hbm_add_cl_resp - send response to fw on client add request
353  *
354  * @dev: the device structure
355  * @addr: me address
356  * @status: response status
357  *
358  * Return: 0 on success and < 0 on failure
359  */
360 static int mei_hbm_add_cl_resp(struct mei_device *dev, u8 addr, u8 status)
361 {
362 	struct mei_msg_hdr mei_hdr;
363 	struct hbm_add_client_response resp;
364 	const size_t len = sizeof(struct hbm_add_client_response);
365 	int ret;
366 
367 	dev_dbg(dev->dev, "adding client response\n");
368 
369 	mei_hbm_hdr(&mei_hdr, len);
370 
371 	memset(&resp, 0, sizeof(struct hbm_add_client_response));
372 	resp.hbm_cmd = MEI_HBM_ADD_CLIENT_RES_CMD;
373 	resp.me_addr = addr;
374 	resp.status  = status;
375 
376 	ret = mei_write_message(dev, &mei_hdr, &resp);
377 	if (ret)
378 		dev_err(dev->dev, "add client response write failed: ret = %d\n",
379 			ret);
380 	return ret;
381 }
382 
383 /**
384  * mei_hbm_fw_add_cl_req - request from the fw to add a client
385  *
386  * @dev: the device structure
387  * @req: add client request
388  *
389  * Return: 0 on success and < 0 on failure
390  */
391 static int mei_hbm_fw_add_cl_req(struct mei_device *dev,
392 			      struct hbm_add_client_request *req)
393 {
394 	int ret;
395 	u8 status = MEI_HBMS_SUCCESS;
396 
397 	BUILD_BUG_ON(sizeof(struct hbm_add_client_request) !=
398 			sizeof(struct hbm_props_response));
399 
400 	ret = mei_hbm_me_cl_add(dev, (struct hbm_props_response *)req);
401 	if (ret)
402 		status = !MEI_HBMS_SUCCESS;
403 
404 	if (dev->dev_state == MEI_DEV_ENABLED)
405 		schedule_work(&dev->bus_rescan_work);
406 
407 	return mei_hbm_add_cl_resp(dev, req->me_addr, status);
408 }
409 
410 /**
411  * mei_hbm_cl_notify_req - send notification request
412  *
413  * @dev: the device structure
414  * @cl: a client to disconnect from
415  * @start: true for start false for stop
416  *
417  * Return: 0 on success and -EIO on write failure
418  */
419 int mei_hbm_cl_notify_req(struct mei_device *dev,
420 			  struct mei_cl *cl, u8 start)
421 {
422 
423 	struct mei_msg_hdr mei_hdr;
424 	struct hbm_notification_request req;
425 	const size_t len = sizeof(struct hbm_notification_request);
426 	int ret;
427 
428 	mei_hbm_hdr(&mei_hdr, len);
429 	mei_hbm_cl_hdr(cl, MEI_HBM_NOTIFY_REQ_CMD, &req, len);
430 
431 	req.start = start;
432 
433 	ret = mei_write_message(dev, &mei_hdr, &req);
434 	if (ret)
435 		dev_err(dev->dev, "notify request failed: ret = %d\n", ret);
436 
437 	return ret;
438 }
439 
440 /**
441  *  notify_res_to_fop - convert notification response to the proper
442  *      notification FOP
443  *
444  * @cmd: client notification start response command
445  *
446  * Return:  MEI_FOP_NOTIFY_START or MEI_FOP_NOTIFY_STOP;
447  */
448 static inline enum mei_cb_file_ops notify_res_to_fop(struct mei_hbm_cl_cmd *cmd)
449 {
450 	struct hbm_notification_response *rs =
451 		(struct hbm_notification_response *)cmd;
452 
453 	return mei_cl_notify_req2fop(rs->start);
454 }
455 
456 /**
457  * mei_hbm_cl_notify_start_res - update the client state according
458  *       notify start response
459  *
460  * @dev: the device structure
461  * @cl: mei host client
462  * @cmd: client notification start response command
463  */
464 static void mei_hbm_cl_notify_start_res(struct mei_device *dev,
465 					struct mei_cl *cl,
466 					struct mei_hbm_cl_cmd *cmd)
467 {
468 	struct hbm_notification_response *rs =
469 		(struct hbm_notification_response *)cmd;
470 
471 	cl_dbg(dev, cl, "hbm: notify start response status=%d\n", rs->status);
472 
473 	if (rs->status == MEI_HBMS_SUCCESS ||
474 	    rs->status == MEI_HBMS_ALREADY_STARTED) {
475 		cl->notify_en = true;
476 		cl->status = 0;
477 	} else {
478 		cl->status = -EINVAL;
479 	}
480 }
481 
482 /**
483  * mei_hbm_cl_notify_stop_res - update the client state according
484  *       notify stop response
485  *
486  * @dev: the device structure
487  * @cl: mei host client
488  * @cmd: client notification stop response command
489  */
490 static void mei_hbm_cl_notify_stop_res(struct mei_device *dev,
491 				       struct mei_cl *cl,
492 				       struct mei_hbm_cl_cmd *cmd)
493 {
494 	struct hbm_notification_response *rs =
495 		(struct hbm_notification_response *)cmd;
496 
497 	cl_dbg(dev, cl, "hbm: notify stop response status=%d\n", rs->status);
498 
499 	if (rs->status == MEI_HBMS_SUCCESS ||
500 	    rs->status == MEI_HBMS_NOT_STARTED) {
501 		cl->notify_en = false;
502 		cl->status = 0;
503 	} else {
504 		/* TODO: spec is not clear yet about other possible issues */
505 		cl->status = -EINVAL;
506 	}
507 }
508 
509 /**
510  * mei_hbm_cl_notify - signal notification event
511  *
512  * @dev: the device structure
513  * @cmd: notification client message
514  */
515 static void mei_hbm_cl_notify(struct mei_device *dev,
516 			      struct mei_hbm_cl_cmd *cmd)
517 {
518 	struct mei_cl *cl;
519 
520 	cl = mei_hbm_cl_find_by_cmd(dev, cmd);
521 	if (cl)
522 		mei_cl_notify(cl);
523 }
524 
525 /**
526  * mei_hbm_prop_req - request property for a single client
527  *
528  * @dev: the device structure
529  * @start_idx: client index to start search
530  *
531  * Return: 0 on success and < 0 on failure
532  */
533 static int mei_hbm_prop_req(struct mei_device *dev, unsigned long start_idx)
534 {
535 	struct mei_msg_hdr mei_hdr;
536 	struct hbm_props_request prop_req;
537 	const size_t len = sizeof(struct hbm_props_request);
538 	unsigned long addr;
539 	int ret;
540 
541 	addr = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX, start_idx);
542 
543 	/* We got all client properties */
544 	if (addr == MEI_CLIENTS_MAX) {
545 		dev->hbm_state = MEI_HBM_STARTED;
546 		mei_host_client_init(dev);
547 
548 		return 0;
549 	}
550 
551 	mei_hbm_hdr(&mei_hdr, len);
552 
553 	memset(&prop_req, 0, sizeof(struct hbm_props_request));
554 
555 	prop_req.hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
556 	prop_req.me_addr = addr;
557 
558 	ret = mei_write_message(dev, &mei_hdr, &prop_req);
559 	if (ret) {
560 		dev_err(dev->dev, "properties request write failed: ret = %d\n",
561 			ret);
562 		return ret;
563 	}
564 
565 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
566 	mei_schedule_stall_timer(dev);
567 
568 	return 0;
569 }
570 
571 /**
572  * mei_hbm_pg - sends pg command
573  *
574  * @dev: the device structure
575  * @pg_cmd: the pg command code
576  *
577  * Return: -EIO on write failure
578  *         -EOPNOTSUPP if the operation is not supported by the protocol
579  */
580 int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
581 {
582 	struct mei_msg_hdr mei_hdr;
583 	struct hbm_power_gate req;
584 	const size_t len = sizeof(struct hbm_power_gate);
585 	int ret;
586 
587 	if (!dev->hbm_f_pg_supported)
588 		return -EOPNOTSUPP;
589 
590 	mei_hbm_hdr(&mei_hdr, len);
591 
592 	memset(&req, 0, len);
593 	req.hbm_cmd = pg_cmd;
594 
595 	ret = mei_write_message(dev, &mei_hdr, &req);
596 	if (ret)
597 		dev_err(dev->dev, "power gate command write failed.\n");
598 	return ret;
599 }
600 EXPORT_SYMBOL_GPL(mei_hbm_pg);
601 
602 /**
603  * mei_hbm_stop_req - send stop request message
604  *
605  * @dev: mei device
606  *
607  * Return: -EIO on write failure
608  */
609 static int mei_hbm_stop_req(struct mei_device *dev)
610 {
611 	struct mei_msg_hdr mei_hdr;
612 	struct hbm_host_stop_request req;
613 	const size_t len = sizeof(struct hbm_host_stop_request);
614 
615 	mei_hbm_hdr(&mei_hdr, len);
616 
617 	memset(&req, 0, len);
618 	req.hbm_cmd = HOST_STOP_REQ_CMD;
619 	req.reason = DRIVER_STOP_REQUEST;
620 
621 	return mei_write_message(dev, &mei_hdr, &req);
622 }
623 
624 /**
625  * mei_hbm_cl_flow_control_req - sends flow control request.
626  *
627  * @dev: the device structure
628  * @cl: client info
629  *
630  * Return: -EIO on write failure
631  */
632 int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
633 {
634 	struct hbm_flow_control req;
635 
636 	cl_dbg(dev, cl, "sending flow control\n");
637 	return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD,
638 				&req, sizeof(req));
639 }
640 
641 /**
642  * mei_hbm_add_single_tx_flow_ctrl_creds - adds single buffer credentials.
643  *
644  * @dev: the device structure
645  * @fctrl: flow control response bus message
646  *
647  * Return: 0 on success, < 0 otherwise
648  */
649 static int mei_hbm_add_single_tx_flow_ctrl_creds(struct mei_device *dev,
650 						 struct hbm_flow_control *fctrl)
651 {
652 	struct mei_me_client *me_cl;
653 	int rets;
654 
655 	me_cl = mei_me_cl_by_id(dev, fctrl->me_addr);
656 	if (!me_cl) {
657 		dev_err(dev->dev, "no such me client %d\n", fctrl->me_addr);
658 		return -ENOENT;
659 	}
660 
661 	if (WARN_ON(me_cl->props.single_recv_buf == 0)) {
662 		rets = -EINVAL;
663 		goto out;
664 	}
665 
666 	me_cl->tx_flow_ctrl_creds++;
667 	dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
668 		fctrl->me_addr, me_cl->tx_flow_ctrl_creds);
669 
670 	rets = 0;
671 out:
672 	mei_me_cl_put(me_cl);
673 	return rets;
674 }
675 
676 /**
677  * mei_hbm_cl_flow_control_res - flow control response from me
678  *
679  * @dev: the device structure
680  * @fctrl: flow control response bus message
681  */
682 static void mei_hbm_cl_tx_flow_ctrl_creds_res(struct mei_device *dev,
683 					       struct hbm_flow_control *fctrl)
684 {
685 	struct mei_cl *cl;
686 
687 	if (!fctrl->host_addr) {
688 		/* single receive buffer */
689 		mei_hbm_add_single_tx_flow_ctrl_creds(dev, fctrl);
690 		return;
691 	}
692 
693 	cl = mei_hbm_cl_find_by_cmd(dev, fctrl);
694 	if (cl) {
695 		cl->tx_flow_ctrl_creds++;
696 		cl_dbg(dev, cl, "flow control creds = %d.\n",
697 				cl->tx_flow_ctrl_creds);
698 	}
699 }
700 
701 
702 /**
703  * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
704  *
705  * @dev: the device structure
706  * @cl: a client to disconnect from
707  *
708  * Return: -EIO on write failure
709  */
710 int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
711 {
712 	struct hbm_client_connect_request req;
713 
714 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD,
715 				&req, sizeof(req));
716 }
717 
718 /**
719  * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
720  *
721  * @dev: the device structure
722  * @cl: a client to disconnect from
723  *
724  * Return: -EIO on write failure
725  */
726 int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
727 {
728 	struct hbm_client_connect_response resp;
729 
730 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD,
731 				&resp, sizeof(resp));
732 }
733 
734 /**
735  * mei_hbm_cl_disconnect_res - update the client state according
736  *       disconnect response
737  *
738  * @dev: the device structure
739  * @cl: mei host client
740  * @cmd: disconnect client response host bus message
741  */
742 static void mei_hbm_cl_disconnect_res(struct mei_device *dev, struct mei_cl *cl,
743 				      struct mei_hbm_cl_cmd *cmd)
744 {
745 	struct hbm_client_connect_response *rs =
746 		(struct hbm_client_connect_response *)cmd;
747 
748 	cl_dbg(dev, cl, "hbm: disconnect response status=%d\n", rs->status);
749 
750 	if (rs->status == MEI_CL_DISCONN_SUCCESS)
751 		cl->state = MEI_FILE_DISCONNECT_REPLY;
752 	cl->status = 0;
753 }
754 
755 /**
756  * mei_hbm_cl_connect_req - send connection request to specific me client
757  *
758  * @dev: the device structure
759  * @cl: a client to connect to
760  *
761  * Return: -EIO on write failure
762  */
763 int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
764 {
765 	struct hbm_client_connect_request req;
766 
767 	return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD,
768 				&req, sizeof(req));
769 }
770 
771 /**
772  * mei_hbm_cl_connect_res - update the client state according
773  *        connection response
774  *
775  * @dev: the device structure
776  * @cl: mei host client
777  * @cmd: connect client response host bus message
778  */
779 static void mei_hbm_cl_connect_res(struct mei_device *dev, struct mei_cl *cl,
780 				   struct mei_hbm_cl_cmd *cmd)
781 {
782 	struct hbm_client_connect_response *rs =
783 		(struct hbm_client_connect_response *)cmd;
784 
785 	cl_dbg(dev, cl, "hbm: connect response status=%s\n",
786 			mei_cl_conn_status_str(rs->status));
787 
788 	if (rs->status == MEI_CL_CONN_SUCCESS)
789 		cl->state = MEI_FILE_CONNECTED;
790 	else {
791 		cl->state = MEI_FILE_DISCONNECT_REPLY;
792 		if (rs->status == MEI_CL_CONN_NOT_FOUND) {
793 			mei_me_cl_del(dev, cl->me_cl);
794 			if (dev->dev_state == MEI_DEV_ENABLED)
795 				schedule_work(&dev->bus_rescan_work);
796 		}
797 	}
798 	cl->status = mei_cl_conn_status_to_errno(rs->status);
799 }
800 
801 /**
802  * mei_hbm_cl_res - process hbm response received on behalf
803  *         an client
804  *
805  * @dev: the device structure
806  * @rs:  hbm client message
807  * @fop_type: file operation type
808  */
809 static void mei_hbm_cl_res(struct mei_device *dev,
810 			   struct mei_hbm_cl_cmd *rs,
811 			   enum mei_cb_file_ops fop_type)
812 {
813 	struct mei_cl *cl;
814 	struct mei_cl_cb *cb, *next;
815 
816 	cl = NULL;
817 	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list, list) {
818 
819 		cl = cb->cl;
820 
821 		if (cb->fop_type != fop_type)
822 			continue;
823 
824 		if (mei_hbm_cl_addr_equal(cl, rs)) {
825 			list_del_init(&cb->list);
826 			break;
827 		}
828 	}
829 
830 	if (!cl)
831 		return;
832 
833 	switch (fop_type) {
834 	case MEI_FOP_CONNECT:
835 		mei_hbm_cl_connect_res(dev, cl, rs);
836 		break;
837 	case MEI_FOP_DISCONNECT:
838 		mei_hbm_cl_disconnect_res(dev, cl, rs);
839 		break;
840 	case MEI_FOP_NOTIFY_START:
841 		mei_hbm_cl_notify_start_res(dev, cl, rs);
842 		break;
843 	case MEI_FOP_NOTIFY_STOP:
844 		mei_hbm_cl_notify_stop_res(dev, cl, rs);
845 		break;
846 	default:
847 		return;
848 	}
849 
850 	cl->timer_count = 0;
851 	wake_up(&cl->wait);
852 }
853 
854 
855 /**
856  * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
857  *  host sends disconnect response
858  *
859  * @dev: the device structure.
860  * @disconnect_req: disconnect request bus message from the me
861  *
862  * Return: -ENOMEM on allocation failure
863  */
864 static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
865 		struct hbm_client_connect_request *disconnect_req)
866 {
867 	struct mei_cl *cl;
868 	struct mei_cl_cb *cb;
869 
870 	cl = mei_hbm_cl_find_by_cmd(dev, disconnect_req);
871 	if (cl) {
872 		cl_warn(dev, cl, "fw disconnect request received\n");
873 		cl->state = MEI_FILE_DISCONNECTING;
874 		cl->timer_count = 0;
875 
876 		cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT_RSP,
877 					       NULL);
878 		if (!cb)
879 			return -ENOMEM;
880 	}
881 	return 0;
882 }
883 
884 /**
885  * mei_hbm_pg_enter_res - PG enter response received
886  *
887  * @dev: the device structure.
888  *
889  * Return: 0 on success, -EPROTO on state mismatch
890  */
891 static int mei_hbm_pg_enter_res(struct mei_device *dev)
892 {
893 	if (mei_pg_state(dev) != MEI_PG_OFF ||
894 	    dev->pg_event != MEI_PG_EVENT_WAIT) {
895 		dev_err(dev->dev, "hbm: pg entry response: state mismatch [%s, %d]\n",
896 			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
897 		return -EPROTO;
898 	}
899 
900 	dev->pg_event = MEI_PG_EVENT_RECEIVED;
901 	wake_up(&dev->wait_pg);
902 
903 	return 0;
904 }
905 
906 /**
907  * mei_hbm_pg_resume - process with PG resume
908  *
909  * @dev: the device structure.
910  */
911 void mei_hbm_pg_resume(struct mei_device *dev)
912 {
913 	pm_request_resume(dev->dev);
914 }
915 EXPORT_SYMBOL_GPL(mei_hbm_pg_resume);
916 
917 /**
918  * mei_hbm_pg_exit_res - PG exit response received
919  *
920  * @dev: the device structure.
921  *
922  * Return: 0 on success, -EPROTO on state mismatch
923  */
924 static int mei_hbm_pg_exit_res(struct mei_device *dev)
925 {
926 	if (mei_pg_state(dev) != MEI_PG_ON ||
927 	    (dev->pg_event != MEI_PG_EVENT_WAIT &&
928 	     dev->pg_event != MEI_PG_EVENT_IDLE)) {
929 		dev_err(dev->dev, "hbm: pg exit response: state mismatch [%s, %d]\n",
930 			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
931 		return -EPROTO;
932 	}
933 
934 	switch (dev->pg_event) {
935 	case MEI_PG_EVENT_WAIT:
936 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
937 		wake_up(&dev->wait_pg);
938 		break;
939 	case MEI_PG_EVENT_IDLE:
940 		/*
941 		* If the driver is not waiting on this then
942 		* this is HW initiated exit from PG.
943 		* Start runtime pm resume sequence to exit from PG.
944 		*/
945 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
946 		mei_hbm_pg_resume(dev);
947 		break;
948 	default:
949 		WARN(1, "hbm: pg exit response: unexpected pg event = %d\n",
950 		     dev->pg_event);
951 		return -EPROTO;
952 	}
953 
954 	return 0;
955 }
956 
957 /**
958  * mei_hbm_config_features - check what hbm features and commands
959  *        are supported by the fw
960  *
961  * @dev: the device structure
962  */
963 static void mei_hbm_config_features(struct mei_device *dev)
964 {
965 	/* Power Gating Isolation Support */
966 	dev->hbm_f_pg_supported = 0;
967 	if (dev->version.major_version > HBM_MAJOR_VERSION_PGI)
968 		dev->hbm_f_pg_supported = 1;
969 
970 	if (dev->version.major_version == HBM_MAJOR_VERSION_PGI &&
971 	    dev->version.minor_version >= HBM_MINOR_VERSION_PGI)
972 		dev->hbm_f_pg_supported = 1;
973 
974 	if (dev->version.major_version >= HBM_MAJOR_VERSION_DC)
975 		dev->hbm_f_dc_supported = 1;
976 
977 	if (dev->version.major_version >= HBM_MAJOR_VERSION_IE)
978 		dev->hbm_f_ie_supported = 1;
979 
980 	/* disconnect on connect timeout instead of link reset */
981 	if (dev->version.major_version >= HBM_MAJOR_VERSION_DOT)
982 		dev->hbm_f_dot_supported = 1;
983 
984 	/* Notification Event Support */
985 	if (dev->version.major_version >= HBM_MAJOR_VERSION_EV)
986 		dev->hbm_f_ev_supported = 1;
987 
988 	/* Fixed Address Client Support */
989 	if (dev->version.major_version >= HBM_MAJOR_VERSION_FA)
990 		dev->hbm_f_fa_supported = 1;
991 
992 	/* OS ver message Support */
993 	if (dev->version.major_version >= HBM_MAJOR_VERSION_OS)
994 		dev->hbm_f_os_supported = 1;
995 }
996 
997 /**
998  * mei_hbm_version_is_supported - checks whether the driver can
999  *     support the hbm version of the device
1000  *
1001  * @dev: the device structure
1002  * Return: true if driver can support hbm version of the device
1003  */
1004 bool mei_hbm_version_is_supported(struct mei_device *dev)
1005 {
1006 	return	(dev->version.major_version < HBM_MAJOR_VERSION) ||
1007 		(dev->version.major_version == HBM_MAJOR_VERSION &&
1008 		 dev->version.minor_version <= HBM_MINOR_VERSION);
1009 }
1010 
1011 /**
1012  * mei_hbm_dispatch - bottom half read routine after ISR to
1013  * handle the read bus message cmd processing.
1014  *
1015  * @dev: the device structure
1016  * @hdr: header of bus message
1017  *
1018  * Return: 0 on success and < 0 on failure
1019  */
1020 int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
1021 {
1022 	struct mei_bus_message *mei_msg;
1023 	struct hbm_host_version_response *version_res;
1024 	struct hbm_props_response *props_res;
1025 	struct hbm_host_enum_response *enum_res;
1026 	struct hbm_add_client_request *add_cl_req;
1027 	int ret;
1028 
1029 	struct mei_hbm_cl_cmd *cl_cmd;
1030 	struct hbm_client_connect_request *disconnect_req;
1031 	struct hbm_flow_control *fctrl;
1032 
1033 	/* read the message to our buffer */
1034 	BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
1035 	mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
1036 	mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
1037 	cl_cmd  = (struct mei_hbm_cl_cmd *)mei_msg;
1038 
1039 	/* ignore spurious message and prevent reset nesting
1040 	 * hbm is put to idle during system reset
1041 	 */
1042 	if (dev->hbm_state == MEI_HBM_IDLE) {
1043 		dev_dbg(dev->dev, "hbm: state is idle ignore spurious messages\n");
1044 		return 0;
1045 	}
1046 
1047 	switch (mei_msg->hbm_cmd) {
1048 	case HOST_START_RES_CMD:
1049 		dev_dbg(dev->dev, "hbm: start: response message received.\n");
1050 
1051 		dev->init_clients_timer = 0;
1052 
1053 		version_res = (struct hbm_host_version_response *)mei_msg;
1054 
1055 		dev_dbg(dev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
1056 				HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
1057 				version_res->me_max_version.major_version,
1058 				version_res->me_max_version.minor_version);
1059 
1060 		if (version_res->host_version_supported) {
1061 			dev->version.major_version = HBM_MAJOR_VERSION;
1062 			dev->version.minor_version = HBM_MINOR_VERSION;
1063 		} else {
1064 			dev->version.major_version =
1065 				version_res->me_max_version.major_version;
1066 			dev->version.minor_version =
1067 				version_res->me_max_version.minor_version;
1068 		}
1069 
1070 		if (!mei_hbm_version_is_supported(dev)) {
1071 			dev_warn(dev->dev, "hbm: start: version mismatch - stopping the driver.\n");
1072 
1073 			dev->hbm_state = MEI_HBM_STOPPED;
1074 			if (mei_hbm_stop_req(dev)) {
1075 				dev_err(dev->dev, "hbm: start: failed to send stop request\n");
1076 				return -EIO;
1077 			}
1078 			break;
1079 		}
1080 
1081 		mei_hbm_config_features(dev);
1082 
1083 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1084 		    dev->hbm_state != MEI_HBM_STARTING) {
1085 			dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
1086 				dev->dev_state, dev->hbm_state);
1087 			return -EPROTO;
1088 		}
1089 
1090 		if (mei_hbm_enum_clients_req(dev)) {
1091 			dev_err(dev->dev, "hbm: start: failed to send enumeration request\n");
1092 			return -EIO;
1093 		}
1094 
1095 		wake_up(&dev->wait_hbm_start);
1096 		break;
1097 
1098 	case CLIENT_CONNECT_RES_CMD:
1099 		dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
1100 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
1101 		break;
1102 
1103 	case CLIENT_DISCONNECT_RES_CMD:
1104 		dev_dbg(dev->dev, "hbm: client disconnect response: message received.\n");
1105 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_DISCONNECT);
1106 		break;
1107 
1108 	case MEI_FLOW_CONTROL_CMD:
1109 		dev_dbg(dev->dev, "hbm: client flow control response: message received.\n");
1110 
1111 		fctrl = (struct hbm_flow_control *)mei_msg;
1112 		mei_hbm_cl_tx_flow_ctrl_creds_res(dev, fctrl);
1113 		break;
1114 
1115 	case MEI_PG_ISOLATION_ENTRY_RES_CMD:
1116 		dev_dbg(dev->dev, "hbm: power gate isolation entry response received\n");
1117 		ret = mei_hbm_pg_enter_res(dev);
1118 		if (ret)
1119 			return ret;
1120 		break;
1121 
1122 	case MEI_PG_ISOLATION_EXIT_REQ_CMD:
1123 		dev_dbg(dev->dev, "hbm: power gate isolation exit request received\n");
1124 		ret = mei_hbm_pg_exit_res(dev);
1125 		if (ret)
1126 			return ret;
1127 		break;
1128 
1129 	case HOST_CLIENT_PROPERTIES_RES_CMD:
1130 		dev_dbg(dev->dev, "hbm: properties response: message received.\n");
1131 
1132 		dev->init_clients_timer = 0;
1133 
1134 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1135 		    dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
1136 			dev_err(dev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
1137 				dev->dev_state, dev->hbm_state);
1138 			return -EPROTO;
1139 		}
1140 
1141 		props_res = (struct hbm_props_response *)mei_msg;
1142 
1143 		if (props_res->status) {
1144 			dev_err(dev->dev, "hbm: properties response: wrong status = %d %s\n",
1145 				props_res->status,
1146 				mei_hbm_status_str(props_res->status));
1147 			return -EPROTO;
1148 		}
1149 
1150 		mei_hbm_me_cl_add(dev, props_res);
1151 
1152 		/* request property for the next client */
1153 		if (mei_hbm_prop_req(dev, props_res->me_addr + 1))
1154 			return -EIO;
1155 
1156 		break;
1157 
1158 	case HOST_ENUM_RES_CMD:
1159 		dev_dbg(dev->dev, "hbm: enumeration response: message received\n");
1160 
1161 		dev->init_clients_timer = 0;
1162 
1163 		enum_res = (struct hbm_host_enum_response *) mei_msg;
1164 		BUILD_BUG_ON(sizeof(dev->me_clients_map)
1165 				< sizeof(enum_res->valid_addresses));
1166 		memcpy(dev->me_clients_map, enum_res->valid_addresses,
1167 				sizeof(enum_res->valid_addresses));
1168 
1169 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1170 		    dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
1171 			dev_err(dev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
1172 				dev->dev_state, dev->hbm_state);
1173 			return -EPROTO;
1174 		}
1175 
1176 		dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
1177 
1178 		/* first property request */
1179 		if (mei_hbm_prop_req(dev, 0))
1180 			return -EIO;
1181 
1182 		break;
1183 
1184 	case HOST_STOP_RES_CMD:
1185 		dev_dbg(dev->dev, "hbm: stop response: message received\n");
1186 
1187 		dev->init_clients_timer = 0;
1188 
1189 		if (dev->hbm_state != MEI_HBM_STOPPED) {
1190 			dev_err(dev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
1191 				dev->dev_state, dev->hbm_state);
1192 			return -EPROTO;
1193 		}
1194 
1195 		dev->dev_state = MEI_DEV_POWER_DOWN;
1196 		dev_info(dev->dev, "hbm: stop response: resetting.\n");
1197 		/* force the reset */
1198 		return -EPROTO;
1199 		break;
1200 
1201 	case CLIENT_DISCONNECT_REQ_CMD:
1202 		dev_dbg(dev->dev, "hbm: disconnect request: message received\n");
1203 
1204 		disconnect_req = (struct hbm_client_connect_request *)mei_msg;
1205 		mei_hbm_fw_disconnect_req(dev, disconnect_req);
1206 		break;
1207 
1208 	case ME_STOP_REQ_CMD:
1209 		dev_dbg(dev->dev, "hbm: stop request: message received\n");
1210 		dev->hbm_state = MEI_HBM_STOPPED;
1211 		if (mei_hbm_stop_req(dev)) {
1212 			dev_err(dev->dev, "hbm: stop request: failed to send stop request\n");
1213 			return -EIO;
1214 		}
1215 		break;
1216 
1217 	case MEI_HBM_ADD_CLIENT_REQ_CMD:
1218 		dev_dbg(dev->dev, "hbm: add client request received\n");
1219 		/*
1220 		 * after the host receives the enum_resp
1221 		 * message clients may be added or removed
1222 		 */
1223 		if (dev->hbm_state <= MEI_HBM_ENUM_CLIENTS ||
1224 		    dev->hbm_state >= MEI_HBM_STOPPED) {
1225 			dev_err(dev->dev, "hbm: add client: state mismatch, [%d, %d]\n",
1226 				dev->dev_state, dev->hbm_state);
1227 			return -EPROTO;
1228 		}
1229 		add_cl_req = (struct hbm_add_client_request *)mei_msg;
1230 		ret = mei_hbm_fw_add_cl_req(dev, add_cl_req);
1231 		if (ret) {
1232 			dev_err(dev->dev, "hbm: add client: failed to send response %d\n",
1233 				ret);
1234 			return -EIO;
1235 		}
1236 		dev_dbg(dev->dev, "hbm: add client request processed\n");
1237 		break;
1238 
1239 	case MEI_HBM_NOTIFY_RES_CMD:
1240 		dev_dbg(dev->dev, "hbm: notify response received\n");
1241 		mei_hbm_cl_res(dev, cl_cmd, notify_res_to_fop(cl_cmd));
1242 		break;
1243 
1244 	case MEI_HBM_NOTIFICATION_CMD:
1245 		dev_dbg(dev->dev, "hbm: notification\n");
1246 		mei_hbm_cl_notify(dev, cl_cmd);
1247 		break;
1248 
1249 	default:
1250 		BUG();
1251 		break;
1252 
1253 	}
1254 	return 0;
1255 }
1256 
1257