xref: /openbmc/linux/drivers/misc/mei/hbm.c (revision 976fa9a3)
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 	default: return "unknown";
56 	}
57 #undef MEI_CL_CCS
58 }
59 
60 const char *mei_hbm_state_str(enum mei_hbm_state state)
61 {
62 #define MEI_HBM_STATE(state) case MEI_HBM_##state: return #state
63 	switch (state) {
64 	MEI_HBM_STATE(IDLE);
65 	MEI_HBM_STATE(STARTING);
66 	MEI_HBM_STATE(STARTED);
67 	MEI_HBM_STATE(ENUM_CLIENTS);
68 	MEI_HBM_STATE(CLIENT_PROPERTIES);
69 	MEI_HBM_STATE(STOPPED);
70 	default:
71 		return "unknown";
72 	}
73 #undef MEI_HBM_STATE
74 }
75 
76 /**
77  * mei_cl_conn_status_to_errno - convert client connect response
78  * status to error code
79  *
80  * @status: client connect response status
81  *
82  * Return: corresponding error code
83  */
84 static int mei_cl_conn_status_to_errno(enum mei_cl_connect_status status)
85 {
86 	switch (status) {
87 	case MEI_CL_CONN_SUCCESS:          return 0;
88 	case MEI_CL_CONN_NOT_FOUND:        return -ENOTTY;
89 	case MEI_CL_CONN_ALREADY_STARTED:  return -EBUSY;
90 	case MEI_CL_CONN_OUT_OF_RESOURCES: return -EBUSY;
91 	case MEI_CL_CONN_MESSAGE_SMALL:    return -EINVAL;
92 	default:                           return -EINVAL;
93 	}
94 }
95 
96 /**
97  * mei_hbm_idle - set hbm to idle state
98  *
99  * @dev: the device structure
100  */
101 void mei_hbm_idle(struct mei_device *dev)
102 {
103 	dev->init_clients_timer = 0;
104 	dev->hbm_state = MEI_HBM_IDLE;
105 }
106 
107 /**
108  * mei_hbm_reset - reset hbm counters and book keeping data structurs
109  *
110  * @dev: the device structure
111  */
112 void mei_hbm_reset(struct mei_device *dev)
113 {
114 	dev->me_client_index = 0;
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 }
136 
137 /**
138  * mei_hbm_cl_hdr - construct client hbm header
139  *
140  * @cl: client
141  * @hbm_cmd: host bus message command
142  * @buf: buffer for cl header
143  * @len: buffer length
144  */
145 static inline
146 void mei_hbm_cl_hdr(struct mei_cl *cl, u8 hbm_cmd, void *buf, size_t len)
147 {
148 	struct mei_hbm_cl_cmd *cmd = buf;
149 
150 	memset(cmd, 0, len);
151 
152 	cmd->hbm_cmd = hbm_cmd;
153 	cmd->host_addr = cl->host_client_id;
154 	cmd->me_addr = cl->me_client_id;
155 }
156 
157 /**
158  * mei_hbm_cl_write - write simple hbm client message
159  *
160  * @dev: the device structure
161  * @cl: client
162  * @hbm_cmd: host bus message command
163  * @len: buffer length
164  *
165  * Return: 0 on success, <0 on failure.
166  */
167 static inline
168 int mei_hbm_cl_write(struct mei_device *dev,
169 		     struct mei_cl *cl, u8 hbm_cmd, size_t len)
170 {
171 	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
172 
173 	mei_hbm_hdr(mei_hdr, len);
174 	mei_hbm_cl_hdr(cl, hbm_cmd, dev->wr_msg.data, len);
175 
176 	return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
177 }
178 
179 /**
180  * mei_hbm_cl_addr_equal - check if the client's and
181  *	the message address match
182  *
183  * @cl: client
184  * @cmd: hbm client message
185  *
186  * Return: true if addresses are the same
187  */
188 static inline
189 bool mei_hbm_cl_addr_equal(struct mei_cl *cl, struct mei_hbm_cl_cmd *cmd)
190 {
191 	return cl->host_client_id == cmd->host_addr &&
192 		cl->me_client_id == cmd->me_addr;
193 }
194 
195 /**
196  * mei_hbm_cl_find_by_cmd - find recipient client
197  *
198  * @dev: the device structure
199  * @buf: a buffer with hbm cl command
200  *
201  * Return: the recipient client or NULL if not found
202  */
203 static inline
204 struct mei_cl *mei_hbm_cl_find_by_cmd(struct mei_device *dev, void *buf)
205 {
206 	struct mei_hbm_cl_cmd *cmd = (struct mei_hbm_cl_cmd *)buf;
207 	struct mei_cl *cl;
208 
209 	list_for_each_entry(cl, &dev->file_list, link)
210 		if (mei_hbm_cl_addr_equal(cl, cmd))
211 			return cl;
212 	return NULL;
213 }
214 
215 
216 /**
217  * mei_hbm_start_wait - wait for start response message.
218  *
219  * @dev: the device structure
220  *
221  * Return: 0 on success and < 0 on failure
222  */
223 int mei_hbm_start_wait(struct mei_device *dev)
224 {
225 	int ret;
226 
227 	if (dev->hbm_state > MEI_HBM_STARTING)
228 		return 0;
229 
230 	mutex_unlock(&dev->device_lock);
231 	ret = wait_event_timeout(dev->wait_hbm_start,
232 			dev->hbm_state != MEI_HBM_STARTING,
233 			mei_secs_to_jiffies(MEI_HBM_TIMEOUT));
234 	mutex_lock(&dev->device_lock);
235 
236 	if (ret == 0 && (dev->hbm_state <= MEI_HBM_STARTING)) {
237 		dev->hbm_state = MEI_HBM_IDLE;
238 		dev_err(dev->dev, "waiting for mei start failed\n");
239 		return -ETIME;
240 	}
241 	return 0;
242 }
243 
244 /**
245  * mei_hbm_start_req - sends start request message.
246  *
247  * @dev: the device structure
248  *
249  * Return: 0 on success and < 0 on failure
250  */
251 int mei_hbm_start_req(struct mei_device *dev)
252 {
253 	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
254 	struct hbm_host_version_request *start_req;
255 	const size_t len = sizeof(struct hbm_host_version_request);
256 	int ret;
257 
258 	mei_hbm_reset(dev);
259 
260 	mei_hbm_hdr(mei_hdr, len);
261 
262 	/* host start message */
263 	start_req = (struct hbm_host_version_request *)dev->wr_msg.data;
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, dev->wr_msg.data);
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 	return 0;
280 }
281 
282 /*
283  * mei_hbm_enum_clients_req - sends enumeration client request message.
284  *
285  * @dev: the device structure
286  *
287  * Return: 0 on success and < 0 on failure
288  */
289 static int mei_hbm_enum_clients_req(struct mei_device *dev)
290 {
291 	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
292 	struct hbm_host_enum_request *enum_req;
293 	const size_t len = sizeof(struct hbm_host_enum_request);
294 	int ret;
295 
296 	/* enumerate clients */
297 	mei_hbm_hdr(mei_hdr, len);
298 
299 	enum_req = (struct hbm_host_enum_request *)dev->wr_msg.data;
300 	memset(enum_req, 0, len);
301 	enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;
302 
303 	ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
304 	if (ret) {
305 		dev_err(dev->dev, "enumeration request write failed: ret = %d.\n",
306 			ret);
307 		return ret;
308 	}
309 	dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
310 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
311 	return 0;
312 }
313 
314 /*
315  * mei_hbm_me_cl_add - add new me client to the list
316  *
317  * @dev: the device structure
318  * @res: hbm property response
319  *
320  * Return: 0 on success and -ENOMEM on allocation failure
321  */
322 
323 static int mei_hbm_me_cl_add(struct mei_device *dev,
324 			     struct hbm_props_response *res)
325 {
326 	struct mei_me_client *me_cl;
327 	const uuid_le *uuid = &res->client_properties.protocol_name;
328 
329 	mei_me_cl_rm_by_uuid(dev, uuid);
330 
331 	me_cl = kzalloc(sizeof(struct mei_me_client), GFP_KERNEL);
332 	if (!me_cl)
333 		return -ENOMEM;
334 
335 	mei_me_cl_init(me_cl);
336 
337 	me_cl->props = res->client_properties;
338 	me_cl->client_id = res->me_addr;
339 	me_cl->mei_flow_ctrl_creds = 0;
340 
341 	mei_me_cl_add(dev, me_cl);
342 
343 	return 0;
344 }
345 
346 /**
347  * mei_hbm_prop_req - request property for a single client
348  *
349  * @dev: the device structure
350  *
351  * Return: 0 on success and < 0 on failure
352  */
353 
354 static int mei_hbm_prop_req(struct mei_device *dev)
355 {
356 
357 	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
358 	struct hbm_props_request *prop_req;
359 	const size_t len = sizeof(struct hbm_props_request);
360 	unsigned long next_client_index;
361 	int ret;
362 
363 	next_client_index = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX,
364 					  dev->me_client_index);
365 
366 	/* We got all client properties */
367 	if (next_client_index == MEI_CLIENTS_MAX) {
368 		dev->hbm_state = MEI_HBM_STARTED;
369 		schedule_work(&dev->init_work);
370 
371 		return 0;
372 	}
373 
374 	mei_hbm_hdr(mei_hdr, len);
375 	prop_req = (struct hbm_props_request *)dev->wr_msg.data;
376 
377 	memset(prop_req, 0, sizeof(struct hbm_props_request));
378 
379 	prop_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
380 	prop_req->me_addr = next_client_index;
381 
382 	ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
383 	if (ret) {
384 		dev_err(dev->dev, "properties request write failed: ret = %d\n",
385 			ret);
386 		return ret;
387 	}
388 
389 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
390 	dev->me_client_index = next_client_index;
391 
392 	return 0;
393 }
394 
395 /*
396  * mei_hbm_pg - sends pg command
397  *
398  * @dev: the device structure
399  * @pg_cmd: the pg command code
400  *
401  * Return: -EIO on write failure
402  *         -EOPNOTSUPP if the operation is not supported by the protocol
403  */
404 int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
405 {
406 	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
407 	struct hbm_power_gate *req;
408 	const size_t len = sizeof(struct hbm_power_gate);
409 	int ret;
410 
411 	if (!dev->hbm_f_pg_supported)
412 		return -EOPNOTSUPP;
413 
414 	mei_hbm_hdr(mei_hdr, len);
415 
416 	req = (struct hbm_power_gate *)dev->wr_msg.data;
417 	memset(req, 0, len);
418 	req->hbm_cmd = pg_cmd;
419 
420 	ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
421 	if (ret)
422 		dev_err(dev->dev, "power gate command write failed.\n");
423 	return ret;
424 }
425 EXPORT_SYMBOL_GPL(mei_hbm_pg);
426 
427 /**
428  * mei_hbm_stop_req - send stop request message
429  *
430  * @dev: mei device
431  *
432  * Return: -EIO on write failure
433  */
434 static int mei_hbm_stop_req(struct mei_device *dev)
435 {
436 	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
437 	struct hbm_host_stop_request *req =
438 			(struct hbm_host_stop_request *)dev->wr_msg.data;
439 	const size_t len = sizeof(struct hbm_host_stop_request);
440 
441 	mei_hbm_hdr(mei_hdr, len);
442 
443 	memset(req, 0, len);
444 	req->hbm_cmd = HOST_STOP_REQ_CMD;
445 	req->reason = DRIVER_STOP_REQUEST;
446 
447 	return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
448 }
449 
450 /**
451  * mei_hbm_cl_flow_control_req - sends flow control request.
452  *
453  * @dev: the device structure
454  * @cl: client info
455  *
456  * Return: -EIO on write failure
457  */
458 int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
459 {
460 	const size_t len = sizeof(struct hbm_flow_control);
461 
462 	cl_dbg(dev, cl, "sending flow control\n");
463 	return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD, len);
464 }
465 
466 /**
467  * mei_hbm_add_single_flow_creds - adds single buffer credentials.
468  *
469  * @dev: the device structure
470  * @flow: flow control.
471  *
472  * Return: 0 on success, < 0 otherwise
473  */
474 static int mei_hbm_add_single_flow_creds(struct mei_device *dev,
475 				  struct hbm_flow_control *flow)
476 {
477 	struct mei_me_client *me_cl;
478 	int rets;
479 
480 	me_cl = mei_me_cl_by_id(dev, flow->me_addr);
481 	if (!me_cl) {
482 		dev_err(dev->dev, "no such me client %d\n",
483 			flow->me_addr);
484 		return -ENOENT;
485 	}
486 
487 	if (WARN_ON(me_cl->props.single_recv_buf == 0)) {
488 		rets = -EINVAL;
489 		goto out;
490 	}
491 
492 	me_cl->mei_flow_ctrl_creds++;
493 	dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
494 	    flow->me_addr, me_cl->mei_flow_ctrl_creds);
495 
496 	rets = 0;
497 out:
498 	mei_me_cl_put(me_cl);
499 	return rets;
500 }
501 
502 /**
503  * mei_hbm_cl_flow_control_res - flow control response from me
504  *
505  * @dev: the device structure
506  * @flow_control: flow control response bus message
507  */
508 static void mei_hbm_cl_flow_control_res(struct mei_device *dev,
509 					struct hbm_flow_control *flow_control)
510 {
511 	struct mei_cl *cl;
512 
513 	if (!flow_control->host_addr) {
514 		/* single receive buffer */
515 		mei_hbm_add_single_flow_creds(dev, flow_control);
516 		return;
517 	}
518 
519 	cl = mei_hbm_cl_find_by_cmd(dev, flow_control);
520 	if (cl) {
521 		cl->mei_flow_ctrl_creds++;
522 		cl_dbg(dev, cl, "flow control creds = %d.\n",
523 				cl->mei_flow_ctrl_creds);
524 	}
525 }
526 
527 
528 /**
529  * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
530  *
531  * @dev: the device structure
532  * @cl: a client to disconnect from
533  *
534  * Return: -EIO on write failure
535  */
536 int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
537 {
538 	const size_t len = sizeof(struct hbm_client_connect_request);
539 
540 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD, len);
541 }
542 
543 /**
544  * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
545  *
546  * @dev: the device structure
547  * @cl: a client to disconnect from
548  *
549  * Return: -EIO on write failure
550  */
551 int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
552 {
553 	const size_t len = sizeof(struct hbm_client_connect_response);
554 
555 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD, len);
556 }
557 
558 /**
559  * mei_hbm_cl_disconnect_res - update the client state according
560  *       disconnect response
561  *
562  * @dev: the device structure
563  * @cl: mei host client
564  * @cmd: disconnect client response host bus message
565  */
566 static void mei_hbm_cl_disconnect_res(struct mei_device *dev, struct mei_cl *cl,
567 				      struct mei_hbm_cl_cmd *cmd)
568 {
569 	struct hbm_client_connect_response *rs =
570 		(struct hbm_client_connect_response *)cmd;
571 
572 	cl_dbg(dev, cl, "hbm: disconnect response status=%d\n", rs->status);
573 
574 	if (rs->status == MEI_CL_DISCONN_SUCCESS)
575 		cl->state = MEI_FILE_DISCONNECTED;
576 	cl->status = 0;
577 }
578 
579 /**
580  * mei_hbm_cl_connect_req - send connection request to specific me client
581  *
582  * @dev: the device structure
583  * @cl: a client to connect to
584  *
585  * Return: -EIO on write failure
586  */
587 int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
588 {
589 	const size_t len = sizeof(struct hbm_client_connect_request);
590 
591 	return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD, len);
592 }
593 
594 /**
595  * mei_hbm_cl_connect_res - update the client state according
596  *        connection response
597  *
598  * @dev: the device structure
599  * @cl: mei host client
600  * @cmd: connect client response host bus message
601  */
602 static void mei_hbm_cl_connect_res(struct mei_device *dev, struct mei_cl *cl,
603 				   struct mei_hbm_cl_cmd *cmd)
604 {
605 	struct hbm_client_connect_response *rs =
606 		(struct hbm_client_connect_response *)cmd;
607 
608 	cl_dbg(dev, cl, "hbm: connect response status=%s\n",
609 			mei_cl_conn_status_str(rs->status));
610 
611 	if (rs->status == MEI_CL_CONN_SUCCESS)
612 		cl->state = MEI_FILE_CONNECTED;
613 	else
614 		cl->state = MEI_FILE_DISCONNECTED;
615 	cl->status = mei_cl_conn_status_to_errno(rs->status);
616 }
617 
618 /**
619  * mei_hbm_cl_res - process hbm response received on behalf
620  *         an client
621  *
622  * @dev: the device structure
623  * @rs:  hbm client message
624  * @fop_type: file operation type
625  */
626 static void mei_hbm_cl_res(struct mei_device *dev,
627 			   struct mei_hbm_cl_cmd *rs,
628 			   enum mei_cb_file_ops fop_type)
629 {
630 	struct mei_cl *cl;
631 	struct mei_cl_cb *cb, *next;
632 
633 	cl = NULL;
634 	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list.list, list) {
635 
636 		cl = cb->cl;
637 
638 		if (cb->fop_type != fop_type)
639 			continue;
640 
641 		if (mei_hbm_cl_addr_equal(cl, rs)) {
642 			list_del_init(&cb->list);
643 			break;
644 		}
645 	}
646 
647 	if (!cl)
648 		return;
649 
650 	switch (fop_type) {
651 	case MEI_FOP_CONNECT:
652 		mei_hbm_cl_connect_res(dev, cl, rs);
653 		break;
654 	case MEI_FOP_DISCONNECT:
655 		mei_hbm_cl_disconnect_res(dev, cl, rs);
656 		break;
657 	default:
658 		return;
659 	}
660 
661 	cl->timer_count = 0;
662 	wake_up(&cl->wait);
663 }
664 
665 
666 /**
667  * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
668  *  host sends disconnect response
669  *
670  * @dev: the device structure.
671  * @disconnect_req: disconnect request bus message from the me
672  *
673  * Return: -ENOMEM on allocation failure
674  */
675 static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
676 		struct hbm_client_connect_request *disconnect_req)
677 {
678 	struct mei_cl *cl;
679 	struct mei_cl_cb *cb;
680 
681 	cl = mei_hbm_cl_find_by_cmd(dev, disconnect_req);
682 	if (cl) {
683 		cl_dbg(dev, cl, "disconnect request received\n");
684 		cl->state = MEI_FILE_DISCONNECTED;
685 		cl->timer_count = 0;
686 
687 		cb = mei_io_cb_init(cl, MEI_FOP_DISCONNECT_RSP, NULL);
688 		if (!cb)
689 			return -ENOMEM;
690 		cl_dbg(dev, cl, "add disconnect response as first\n");
691 		list_add(&cb->list, &dev->ctrl_wr_list.list);
692 	}
693 	return 0;
694 }
695 
696 /**
697  * mei_hbm_config_features - check what hbm features and commands
698  *        are supported by the fw
699  *
700  * @dev: the device structure
701  */
702 static void mei_hbm_config_features(struct mei_device *dev)
703 {
704 	/* Power Gating Isolation Support */
705 	dev->hbm_f_pg_supported = 0;
706 	if (dev->version.major_version > HBM_MAJOR_VERSION_PGI)
707 		dev->hbm_f_pg_supported = 1;
708 
709 	if (dev->version.major_version == HBM_MAJOR_VERSION_PGI &&
710 	    dev->version.minor_version >= HBM_MINOR_VERSION_PGI)
711 		dev->hbm_f_pg_supported = 1;
712 }
713 
714 /**
715  * mei_hbm_version_is_supported - checks whether the driver can
716  *     support the hbm version of the device
717  *
718  * @dev: the device structure
719  * Return: true if driver can support hbm version of the device
720  */
721 bool mei_hbm_version_is_supported(struct mei_device *dev)
722 {
723 	return	(dev->version.major_version < HBM_MAJOR_VERSION) ||
724 		(dev->version.major_version == HBM_MAJOR_VERSION &&
725 		 dev->version.minor_version <= HBM_MINOR_VERSION);
726 }
727 
728 /**
729  * mei_hbm_dispatch - bottom half read routine after ISR to
730  * handle the read bus message cmd processing.
731  *
732  * @dev: the device structure
733  * @hdr: header of bus message
734  *
735  * Return: 0 on success and < 0 on failure
736  */
737 int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
738 {
739 	struct mei_bus_message *mei_msg;
740 	struct hbm_host_version_response *version_res;
741 	struct hbm_props_response *props_res;
742 	struct hbm_host_enum_response *enum_res;
743 
744 	struct mei_hbm_cl_cmd *cl_cmd;
745 	struct hbm_client_connect_request *disconnect_req;
746 	struct hbm_flow_control *flow_control;
747 
748 	/* read the message to our buffer */
749 	BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
750 	mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
751 	mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
752 	cl_cmd  = (struct mei_hbm_cl_cmd *)mei_msg;
753 
754 	/* ignore spurious message and prevent reset nesting
755 	 * hbm is put to idle during system reset
756 	 */
757 	if (dev->hbm_state == MEI_HBM_IDLE) {
758 		dev_dbg(dev->dev, "hbm: state is idle ignore spurious messages\n");
759 		return 0;
760 	}
761 
762 	switch (mei_msg->hbm_cmd) {
763 	case HOST_START_RES_CMD:
764 		dev_dbg(dev->dev, "hbm: start: response message received.\n");
765 
766 		dev->init_clients_timer = 0;
767 
768 		version_res = (struct hbm_host_version_response *)mei_msg;
769 
770 		dev_dbg(dev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
771 				HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
772 				version_res->me_max_version.major_version,
773 				version_res->me_max_version.minor_version);
774 
775 		if (version_res->host_version_supported) {
776 			dev->version.major_version = HBM_MAJOR_VERSION;
777 			dev->version.minor_version = HBM_MINOR_VERSION;
778 		} else {
779 			dev->version.major_version =
780 				version_res->me_max_version.major_version;
781 			dev->version.minor_version =
782 				version_res->me_max_version.minor_version;
783 		}
784 
785 		if (!mei_hbm_version_is_supported(dev)) {
786 			dev_warn(dev->dev, "hbm: start: version mismatch - stopping the driver.\n");
787 
788 			dev->hbm_state = MEI_HBM_STOPPED;
789 			if (mei_hbm_stop_req(dev)) {
790 				dev_err(dev->dev, "hbm: start: failed to send stop request\n");
791 				return -EIO;
792 			}
793 			break;
794 		}
795 
796 		mei_hbm_config_features(dev);
797 
798 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
799 		    dev->hbm_state != MEI_HBM_STARTING) {
800 			dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
801 				dev->dev_state, dev->hbm_state);
802 			return -EPROTO;
803 		}
804 
805 		if (mei_hbm_enum_clients_req(dev)) {
806 			dev_err(dev->dev, "hbm: start: failed to send enumeration request\n");
807 			return -EIO;
808 		}
809 
810 		wake_up(&dev->wait_hbm_start);
811 		break;
812 
813 	case CLIENT_CONNECT_RES_CMD:
814 		dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
815 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
816 		break;
817 
818 	case CLIENT_DISCONNECT_RES_CMD:
819 		dev_dbg(dev->dev, "hbm: client disconnect response: message received.\n");
820 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_DISCONNECT);
821 		break;
822 
823 	case MEI_FLOW_CONTROL_CMD:
824 		dev_dbg(dev->dev, "hbm: client flow control response: message received.\n");
825 
826 		flow_control = (struct hbm_flow_control *) mei_msg;
827 		mei_hbm_cl_flow_control_res(dev, flow_control);
828 		break;
829 
830 	case MEI_PG_ISOLATION_ENTRY_RES_CMD:
831 		dev_dbg(dev->dev, "power gate isolation entry response received\n");
832 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
833 		if (waitqueue_active(&dev->wait_pg))
834 			wake_up(&dev->wait_pg);
835 		break;
836 
837 	case MEI_PG_ISOLATION_EXIT_REQ_CMD:
838 		dev_dbg(dev->dev, "power gate isolation exit request received\n");
839 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
840 		if (waitqueue_active(&dev->wait_pg))
841 			wake_up(&dev->wait_pg);
842 		else
843 			/*
844 			* If the driver is not waiting on this then
845 			* this is HW initiated exit from PG.
846 			* Start runtime pm resume sequence to exit from PG.
847 			*/
848 			pm_request_resume(dev->dev);
849 		break;
850 
851 	case HOST_CLIENT_PROPERTIES_RES_CMD:
852 		dev_dbg(dev->dev, "hbm: properties response: message received.\n");
853 
854 		dev->init_clients_timer = 0;
855 
856 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
857 		    dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
858 			dev_err(dev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
859 				dev->dev_state, dev->hbm_state);
860 			return -EPROTO;
861 		}
862 
863 		props_res = (struct hbm_props_response *)mei_msg;
864 
865 		if (props_res->status) {
866 			dev_err(dev->dev, "hbm: properties response: wrong status = %d %s\n",
867 				props_res->status,
868 				mei_hbm_status_str(props_res->status));
869 			return -EPROTO;
870 		}
871 
872 		mei_hbm_me_cl_add(dev, props_res);
873 
874 		dev->me_client_index++;
875 
876 		/* request property for the next client */
877 		if (mei_hbm_prop_req(dev))
878 			return -EIO;
879 
880 		break;
881 
882 	case HOST_ENUM_RES_CMD:
883 		dev_dbg(dev->dev, "hbm: enumeration response: message received\n");
884 
885 		dev->init_clients_timer = 0;
886 
887 		enum_res = (struct hbm_host_enum_response *) mei_msg;
888 		BUILD_BUG_ON(sizeof(dev->me_clients_map)
889 				< sizeof(enum_res->valid_addresses));
890 		memcpy(dev->me_clients_map, enum_res->valid_addresses,
891 				sizeof(enum_res->valid_addresses));
892 
893 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
894 		    dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
895 			dev_err(dev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
896 				dev->dev_state, dev->hbm_state);
897 			return -EPROTO;
898 		}
899 
900 		dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
901 
902 		/* first property request */
903 		if (mei_hbm_prop_req(dev))
904 			return -EIO;
905 
906 		break;
907 
908 	case HOST_STOP_RES_CMD:
909 		dev_dbg(dev->dev, "hbm: stop response: message received\n");
910 
911 		dev->init_clients_timer = 0;
912 
913 		if (dev->hbm_state != MEI_HBM_STOPPED) {
914 			dev_err(dev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
915 				dev->dev_state, dev->hbm_state);
916 			return -EPROTO;
917 		}
918 
919 		dev->dev_state = MEI_DEV_POWER_DOWN;
920 		dev_info(dev->dev, "hbm: stop response: resetting.\n");
921 		/* force the reset */
922 		return -EPROTO;
923 		break;
924 
925 	case CLIENT_DISCONNECT_REQ_CMD:
926 		dev_dbg(dev->dev, "hbm: disconnect request: message received\n");
927 
928 		disconnect_req = (struct hbm_client_connect_request *)mei_msg;
929 		mei_hbm_fw_disconnect_req(dev, disconnect_req);
930 		break;
931 
932 	case ME_STOP_REQ_CMD:
933 		dev_dbg(dev->dev, "hbm: stop request: message received\n");
934 		dev->hbm_state = MEI_HBM_STOPPED;
935 		if (mei_hbm_stop_req(dev)) {
936 			dev_err(dev->dev, "hbm: stop request: failed to send stop request\n");
937 			return -EIO;
938 		}
939 		break;
940 	default:
941 		BUG();
942 		break;
943 
944 	}
945 	return 0;
946 }
947 
948