xref: /openbmc/linux/drivers/misc/mei/hbm.c (revision 82003e04)
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
170 int mei_hbm_cl_write(struct mei_device *dev, struct mei_cl *cl,
171 		     u8 hbm_cmd, u8 *buf, size_t len)
172 {
173 	struct mei_msg_hdr mei_hdr;
174 
175 	mei_hbm_hdr(&mei_hdr, len);
176 	mei_hbm_cl_hdr(cl, hbm_cmd, buf, len);
177 
178 	return mei_write_message(dev, &mei_hdr, buf);
179 }
180 
181 /**
182  * mei_hbm_cl_addr_equal - check if the client's and
183  *	the message address match
184  *
185  * @cl: client
186  * @cmd: hbm client message
187  *
188  * Return: true if addresses are the same
189  */
190 static inline
191 bool mei_hbm_cl_addr_equal(struct mei_cl *cl, struct mei_hbm_cl_cmd *cmd)
192 {
193 	return  mei_cl_host_addr(cl) == cmd->host_addr &&
194 		mei_cl_me_id(cl) == cmd->me_addr;
195 }
196 
197 /**
198  * mei_hbm_cl_find_by_cmd - find recipient client
199  *
200  * @dev: the device structure
201  * @buf: a buffer with hbm cl command
202  *
203  * Return: the recipient client or NULL if not found
204  */
205 static inline
206 struct mei_cl *mei_hbm_cl_find_by_cmd(struct mei_device *dev, void *buf)
207 {
208 	struct mei_hbm_cl_cmd *cmd = (struct mei_hbm_cl_cmd *)buf;
209 	struct mei_cl *cl;
210 
211 	list_for_each_entry(cl, &dev->file_list, link)
212 		if (mei_hbm_cl_addr_equal(cl, cmd))
213 			return cl;
214 	return NULL;
215 }
216 
217 
218 /**
219  * mei_hbm_start_wait - wait for start response message.
220  *
221  * @dev: the device structure
222  *
223  * Return: 0 on success and < 0 on failure
224  */
225 int mei_hbm_start_wait(struct mei_device *dev)
226 {
227 	int ret;
228 
229 	if (dev->hbm_state > MEI_HBM_STARTING)
230 		return 0;
231 
232 	mutex_unlock(&dev->device_lock);
233 	ret = wait_event_timeout(dev->wait_hbm_start,
234 			dev->hbm_state != MEI_HBM_STARTING,
235 			mei_secs_to_jiffies(MEI_HBM_TIMEOUT));
236 	mutex_lock(&dev->device_lock);
237 
238 	if (ret == 0 && (dev->hbm_state <= MEI_HBM_STARTING)) {
239 		dev->hbm_state = MEI_HBM_IDLE;
240 		dev_err(dev->dev, "waiting for mei start failed\n");
241 		return -ETIME;
242 	}
243 	return 0;
244 }
245 
246 /**
247  * mei_hbm_start_req - sends start request message.
248  *
249  * @dev: the device structure
250  *
251  * Return: 0 on success and < 0 on failure
252  */
253 int mei_hbm_start_req(struct mei_device *dev)
254 {
255 	struct mei_msg_hdr mei_hdr;
256 	struct hbm_host_version_request start_req;
257 	const size_t len = sizeof(struct hbm_host_version_request);
258 	int ret;
259 
260 	mei_hbm_reset(dev);
261 
262 	mei_hbm_hdr(&mei_hdr, len);
263 
264 	/* host start message */
265 	memset(&start_req, 0, len);
266 	start_req.hbm_cmd = HOST_START_REQ_CMD;
267 	start_req.host_version.major_version = HBM_MAJOR_VERSION;
268 	start_req.host_version.minor_version = HBM_MINOR_VERSION;
269 
270 	dev->hbm_state = MEI_HBM_IDLE;
271 	ret = mei_write_message(dev, &mei_hdr, &start_req);
272 	if (ret) {
273 		dev_err(dev->dev, "version message write failed: ret = %d\n",
274 			ret);
275 		return ret;
276 	}
277 
278 	dev->hbm_state = MEI_HBM_STARTING;
279 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
280 	mei_schedule_stall_timer(dev);
281 	return 0;
282 }
283 
284 /**
285  * mei_hbm_enum_clients_req - sends enumeration client request message.
286  *
287  * @dev: the device structure
288  *
289  * Return: 0 on success and < 0 on failure
290  */
291 static int mei_hbm_enum_clients_req(struct mei_device *dev)
292 {
293 	struct mei_msg_hdr mei_hdr;
294 	struct hbm_host_enum_request enum_req;
295 	const size_t len = sizeof(struct hbm_host_enum_request);
296 	int ret;
297 
298 	/* enumerate clients */
299 	mei_hbm_hdr(&mei_hdr, len);
300 
301 	memset(&enum_req, 0, len);
302 	enum_req.hbm_cmd = HOST_ENUM_REQ_CMD;
303 	enum_req.flags |= dev->hbm_f_dc_supported ?
304 			  MEI_HBM_ENUM_F_ALLOW_ADD : 0;
305 	enum_req.flags |= dev->hbm_f_ie_supported ?
306 			  MEI_HBM_ENUM_F_IMMEDIATE_ENUM : 0;
307 
308 	ret = mei_write_message(dev, &mei_hdr, &enum_req);
309 	if (ret) {
310 		dev_err(dev->dev, "enumeration request write failed: ret = %d.\n",
311 			ret);
312 		return ret;
313 	}
314 	dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
315 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
316 	mei_schedule_stall_timer(dev);
317 	return 0;
318 }
319 
320 /**
321  * mei_hbm_me_cl_add - add new me client to the list
322  *
323  * @dev: the device structure
324  * @res: hbm property response
325  *
326  * Return: 0 on success and -ENOMEM on allocation failure
327  */
328 
329 static int mei_hbm_me_cl_add(struct mei_device *dev,
330 			     struct hbm_props_response *res)
331 {
332 	struct mei_me_client *me_cl;
333 	const uuid_le *uuid = &res->client_properties.protocol_name;
334 
335 	mei_me_cl_rm_by_uuid(dev, uuid);
336 
337 	me_cl = kzalloc(sizeof(struct mei_me_client), GFP_KERNEL);
338 	if (!me_cl)
339 		return -ENOMEM;
340 
341 	mei_me_cl_init(me_cl);
342 
343 	me_cl->props = res->client_properties;
344 	me_cl->client_id = res->me_addr;
345 	me_cl->tx_flow_ctrl_creds = 0;
346 
347 	mei_me_cl_add(dev, me_cl);
348 
349 	return 0;
350 }
351 
352 /**
353  * mei_hbm_add_cl_resp - send response to fw on client add request
354  *
355  * @dev: the device structure
356  * @addr: me address
357  * @status: response status
358  *
359  * Return: 0 on success and < 0 on failure
360  */
361 static int mei_hbm_add_cl_resp(struct mei_device *dev, u8 addr, u8 status)
362 {
363 	struct mei_msg_hdr mei_hdr;
364 	struct hbm_add_client_response resp;
365 	const size_t len = sizeof(struct hbm_add_client_response);
366 	int ret;
367 
368 	dev_dbg(dev->dev, "adding client response\n");
369 
370 	mei_hbm_hdr(&mei_hdr, len);
371 
372 	memset(&resp, 0, sizeof(struct hbm_add_client_response));
373 	resp.hbm_cmd = MEI_HBM_ADD_CLIENT_RES_CMD;
374 	resp.me_addr = addr;
375 	resp.status  = status;
376 
377 	ret = mei_write_message(dev, &mei_hdr, &resp);
378 	if (ret)
379 		dev_err(dev->dev, "add client response write failed: ret = %d\n",
380 			ret);
381 	return ret;
382 }
383 
384 /**
385  * mei_hbm_fw_add_cl_req - request from the fw to add a client
386  *
387  * @dev: the device structure
388  * @req: add client request
389  *
390  * Return: 0 on success and < 0 on failure
391  */
392 static int mei_hbm_fw_add_cl_req(struct mei_device *dev,
393 			      struct hbm_add_client_request *req)
394 {
395 	int ret;
396 	u8 status = MEI_HBMS_SUCCESS;
397 
398 	BUILD_BUG_ON(sizeof(struct hbm_add_client_request) !=
399 			sizeof(struct hbm_props_response));
400 
401 	ret = mei_hbm_me_cl_add(dev, (struct hbm_props_response *)req);
402 	if (ret)
403 		status = !MEI_HBMS_SUCCESS;
404 
405 	if (dev->dev_state == MEI_DEV_ENABLED)
406 		schedule_work(&dev->bus_rescan_work);
407 
408 	return mei_hbm_add_cl_resp(dev, req->me_addr, status);
409 }
410 
411 /**
412  * mei_hbm_cl_notify_req - send notification request
413  *
414  * @dev: the device structure
415  * @cl: a client to disconnect from
416  * @start: true for start false for stop
417  *
418  * Return: 0 on success and -EIO on write failure
419  */
420 int mei_hbm_cl_notify_req(struct mei_device *dev,
421 			  struct mei_cl *cl, u8 start)
422 {
423 
424 	struct mei_msg_hdr mei_hdr;
425 	struct hbm_notification_request req;
426 	const size_t len = sizeof(struct hbm_notification_request);
427 	int ret;
428 
429 	mei_hbm_hdr(&mei_hdr, len);
430 	mei_hbm_cl_hdr(cl, MEI_HBM_NOTIFY_REQ_CMD, &req, len);
431 
432 	req.start = start;
433 
434 	ret = mei_write_message(dev, &mei_hdr, &req);
435 	if (ret)
436 		dev_err(dev->dev, "notify request failed: ret = %d\n", ret);
437 
438 	return ret;
439 }
440 
441 /**
442  *  notify_res_to_fop - convert notification response to the proper
443  *      notification FOP
444  *
445  * @cmd: client notification start response command
446  *
447  * Return:  MEI_FOP_NOTIFY_START or MEI_FOP_NOTIFY_STOP;
448  */
449 static inline enum mei_cb_file_ops notify_res_to_fop(struct mei_hbm_cl_cmd *cmd)
450 {
451 	struct hbm_notification_response *rs =
452 		(struct hbm_notification_response *)cmd;
453 
454 	return mei_cl_notify_req2fop(rs->start);
455 }
456 
457 /**
458  * mei_hbm_cl_notify_start_res - update the client state according
459  *       notify start response
460  *
461  * @dev: the device structure
462  * @cl: mei host client
463  * @cmd: client notification start response command
464  */
465 static void mei_hbm_cl_notify_start_res(struct mei_device *dev,
466 					struct mei_cl *cl,
467 					struct mei_hbm_cl_cmd *cmd)
468 {
469 	struct hbm_notification_response *rs =
470 		(struct hbm_notification_response *)cmd;
471 
472 	cl_dbg(dev, cl, "hbm: notify start response status=%d\n", rs->status);
473 
474 	if (rs->status == MEI_HBMS_SUCCESS ||
475 	    rs->status == MEI_HBMS_ALREADY_STARTED) {
476 		cl->notify_en = true;
477 		cl->status = 0;
478 	} else {
479 		cl->status = -EINVAL;
480 	}
481 }
482 
483 /**
484  * mei_hbm_cl_notify_stop_res - update the client state according
485  *       notify stop response
486  *
487  * @dev: the device structure
488  * @cl: mei host client
489  * @cmd: client notification stop response command
490  */
491 static void mei_hbm_cl_notify_stop_res(struct mei_device *dev,
492 				       struct mei_cl *cl,
493 				       struct mei_hbm_cl_cmd *cmd)
494 {
495 	struct hbm_notification_response *rs =
496 		(struct hbm_notification_response *)cmd;
497 
498 	cl_dbg(dev, cl, "hbm: notify stop response status=%d\n", rs->status);
499 
500 	if (rs->status == MEI_HBMS_SUCCESS ||
501 	    rs->status == MEI_HBMS_NOT_STARTED) {
502 		cl->notify_en = false;
503 		cl->status = 0;
504 	} else {
505 		/* TODO: spec is not clear yet about other possible issues */
506 		cl->status = -EINVAL;
507 	}
508 }
509 
510 /**
511  * mei_hbm_cl_notify - signal notification event
512  *
513  * @dev: the device structure
514  * @cmd: notification client message
515  */
516 static void mei_hbm_cl_notify(struct mei_device *dev,
517 			      struct mei_hbm_cl_cmd *cmd)
518 {
519 	struct mei_cl *cl;
520 
521 	cl = mei_hbm_cl_find_by_cmd(dev, cmd);
522 	if (cl)
523 		mei_cl_notify(cl);
524 }
525 
526 /**
527  * mei_hbm_prop_req - request property for a single client
528  *
529  * @dev: the device structure
530  * @start_idx: client index to start search
531  *
532  * Return: 0 on success and < 0 on failure
533  */
534 static int mei_hbm_prop_req(struct mei_device *dev, unsigned long start_idx)
535 {
536 	struct mei_msg_hdr mei_hdr;
537 	struct hbm_props_request prop_req;
538 	const size_t len = sizeof(struct hbm_props_request);
539 	unsigned long addr;
540 	int ret;
541 
542 	addr = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX, start_idx);
543 
544 	/* We got all client properties */
545 	if (addr == MEI_CLIENTS_MAX) {
546 		dev->hbm_state = MEI_HBM_STARTED;
547 		mei_host_client_init(dev);
548 
549 		return 0;
550 	}
551 
552 	mei_hbm_hdr(&mei_hdr, len);
553 
554 	memset(&prop_req, 0, sizeof(struct hbm_props_request));
555 
556 	prop_req.hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
557 	prop_req.me_addr = addr;
558 
559 	ret = mei_write_message(dev, &mei_hdr, &prop_req);
560 	if (ret) {
561 		dev_err(dev->dev, "properties request write failed: ret = %d\n",
562 			ret);
563 		return ret;
564 	}
565 
566 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
567 	mei_schedule_stall_timer(dev);
568 
569 	return 0;
570 }
571 
572 /**
573  * mei_hbm_pg - sends pg command
574  *
575  * @dev: the device structure
576  * @pg_cmd: the pg command code
577  *
578  * Return: -EIO on write failure
579  *         -EOPNOTSUPP if the operation is not supported by the protocol
580  */
581 int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
582 {
583 	struct mei_msg_hdr mei_hdr;
584 	struct hbm_power_gate req;
585 	const size_t len = sizeof(struct hbm_power_gate);
586 	int ret;
587 
588 	if (!dev->hbm_f_pg_supported)
589 		return -EOPNOTSUPP;
590 
591 	mei_hbm_hdr(&mei_hdr, len);
592 
593 	memset(&req, 0, len);
594 	req.hbm_cmd = pg_cmd;
595 
596 	ret = mei_write_message(dev, &mei_hdr, &req);
597 	if (ret)
598 		dev_err(dev->dev, "power gate command write failed.\n");
599 	return ret;
600 }
601 EXPORT_SYMBOL_GPL(mei_hbm_pg);
602 
603 /**
604  * mei_hbm_stop_req - send stop request message
605  *
606  * @dev: mei device
607  *
608  * Return: -EIO on write failure
609  */
610 static int mei_hbm_stop_req(struct mei_device *dev)
611 {
612 	struct mei_msg_hdr mei_hdr;
613 	struct hbm_host_stop_request req;
614 	const size_t len = sizeof(struct hbm_host_stop_request);
615 
616 	mei_hbm_hdr(&mei_hdr, len);
617 
618 	memset(&req, 0, len);
619 	req.hbm_cmd = HOST_STOP_REQ_CMD;
620 	req.reason = DRIVER_STOP_REQUEST;
621 
622 	return mei_write_message(dev, &mei_hdr, &req);
623 }
624 
625 /**
626  * mei_hbm_cl_flow_control_req - sends flow control request.
627  *
628  * @dev: the device structure
629  * @cl: client info
630  *
631  * Return: -EIO on write failure
632  */
633 int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
634 {
635 	const size_t len = sizeof(struct hbm_flow_control);
636 	u8 buf[len];
637 
638 	cl_dbg(dev, cl, "sending flow control\n");
639 	return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD, buf, len);
640 }
641 
642 /**
643  * mei_hbm_add_single_tx_flow_ctrl_creds - adds single buffer credentials.
644  *
645  * @dev: the device structure
646  * @fctrl: flow control response bus message
647  *
648  * Return: 0 on success, < 0 otherwise
649  */
650 static int mei_hbm_add_single_tx_flow_ctrl_creds(struct mei_device *dev,
651 						 struct hbm_flow_control *fctrl)
652 {
653 	struct mei_me_client *me_cl;
654 	int rets;
655 
656 	me_cl = mei_me_cl_by_id(dev, fctrl->me_addr);
657 	if (!me_cl) {
658 		dev_err(dev->dev, "no such me client %d\n", fctrl->me_addr);
659 		return -ENOENT;
660 	}
661 
662 	if (WARN_ON(me_cl->props.single_recv_buf == 0)) {
663 		rets = -EINVAL;
664 		goto out;
665 	}
666 
667 	me_cl->tx_flow_ctrl_creds++;
668 	dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
669 		fctrl->me_addr, me_cl->tx_flow_ctrl_creds);
670 
671 	rets = 0;
672 out:
673 	mei_me_cl_put(me_cl);
674 	return rets;
675 }
676 
677 /**
678  * mei_hbm_cl_flow_control_res - flow control response from me
679  *
680  * @dev: the device structure
681  * @fctrl: flow control response bus message
682  */
683 static void mei_hbm_cl_tx_flow_ctrl_creds_res(struct mei_device *dev,
684 					       struct hbm_flow_control *fctrl)
685 {
686 	struct mei_cl *cl;
687 
688 	if (!fctrl->host_addr) {
689 		/* single receive buffer */
690 		mei_hbm_add_single_tx_flow_ctrl_creds(dev, fctrl);
691 		return;
692 	}
693 
694 	cl = mei_hbm_cl_find_by_cmd(dev, fctrl);
695 	if (cl) {
696 		cl->tx_flow_ctrl_creds++;
697 		cl_dbg(dev, cl, "flow control creds = %d.\n",
698 				cl->tx_flow_ctrl_creds);
699 	}
700 }
701 
702 
703 /**
704  * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
705  *
706  * @dev: the device structure
707  * @cl: a client to disconnect from
708  *
709  * Return: -EIO on write failure
710  */
711 int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
712 {
713 	const size_t len = sizeof(struct hbm_client_connect_request);
714 	u8 buf[len];
715 
716 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD, buf, len);
717 }
718 
719 /**
720  * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
721  *
722  * @dev: the device structure
723  * @cl: a client to disconnect from
724  *
725  * Return: -EIO on write failure
726  */
727 int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
728 {
729 	const size_t len = sizeof(struct hbm_client_connect_response);
730 	u8 buf[len];
731 
732 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD, buf, len);
733 }
734 
735 /**
736  * mei_hbm_cl_disconnect_res - update the client state according
737  *       disconnect response
738  *
739  * @dev: the device structure
740  * @cl: mei host client
741  * @cmd: disconnect client response host bus message
742  */
743 static void mei_hbm_cl_disconnect_res(struct mei_device *dev, struct mei_cl *cl,
744 				      struct mei_hbm_cl_cmd *cmd)
745 {
746 	struct hbm_client_connect_response *rs =
747 		(struct hbm_client_connect_response *)cmd;
748 
749 	cl_dbg(dev, cl, "hbm: disconnect response status=%d\n", rs->status);
750 
751 	if (rs->status == MEI_CL_DISCONN_SUCCESS)
752 		cl->state = MEI_FILE_DISCONNECT_REPLY;
753 	cl->status = 0;
754 }
755 
756 /**
757  * mei_hbm_cl_connect_req - send connection request to specific me client
758  *
759  * @dev: the device structure
760  * @cl: a client to connect to
761  *
762  * Return: -EIO on write failure
763  */
764 int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
765 {
766 	const size_t len = sizeof(struct hbm_client_connect_request);
767 	u8 buf[len];
768 
769 	return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD, buf, len);
770 }
771 
772 /**
773  * mei_hbm_cl_connect_res - update the client state according
774  *        connection response
775  *
776  * @dev: the device structure
777  * @cl: mei host client
778  * @cmd: connect client response host bus message
779  */
780 static void mei_hbm_cl_connect_res(struct mei_device *dev, struct mei_cl *cl,
781 				   struct mei_hbm_cl_cmd *cmd)
782 {
783 	struct hbm_client_connect_response *rs =
784 		(struct hbm_client_connect_response *)cmd;
785 
786 	cl_dbg(dev, cl, "hbm: connect response status=%s\n",
787 			mei_cl_conn_status_str(rs->status));
788 
789 	if (rs->status == MEI_CL_CONN_SUCCESS)
790 		cl->state = MEI_FILE_CONNECTED;
791 	else {
792 		cl->state = MEI_FILE_DISCONNECT_REPLY;
793 		if (rs->status == MEI_CL_CONN_NOT_FOUND) {
794 			mei_me_cl_del(dev, cl->me_cl);
795 			if (dev->dev_state == MEI_DEV_ENABLED)
796 				schedule_work(&dev->bus_rescan_work);
797 		}
798 	}
799 	cl->status = mei_cl_conn_status_to_errno(rs->status);
800 }
801 
802 /**
803  * mei_hbm_cl_res - process hbm response received on behalf
804  *         an client
805  *
806  * @dev: the device structure
807  * @rs:  hbm client message
808  * @fop_type: file operation type
809  */
810 static void mei_hbm_cl_res(struct mei_device *dev,
811 			   struct mei_hbm_cl_cmd *rs,
812 			   enum mei_cb_file_ops fop_type)
813 {
814 	struct mei_cl *cl;
815 	struct mei_cl_cb *cb, *next;
816 
817 	cl = NULL;
818 	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list.list, list) {
819 
820 		cl = cb->cl;
821 
822 		if (cb->fop_type != fop_type)
823 			continue;
824 
825 		if (mei_hbm_cl_addr_equal(cl, rs)) {
826 			list_del_init(&cb->list);
827 			break;
828 		}
829 	}
830 
831 	if (!cl)
832 		return;
833 
834 	switch (fop_type) {
835 	case MEI_FOP_CONNECT:
836 		mei_hbm_cl_connect_res(dev, cl, rs);
837 		break;
838 	case MEI_FOP_DISCONNECT:
839 		mei_hbm_cl_disconnect_res(dev, cl, rs);
840 		break;
841 	case MEI_FOP_NOTIFY_START:
842 		mei_hbm_cl_notify_start_res(dev, cl, rs);
843 		break;
844 	case MEI_FOP_NOTIFY_STOP:
845 		mei_hbm_cl_notify_stop_res(dev, cl, rs);
846 		break;
847 	default:
848 		return;
849 	}
850 
851 	cl->timer_count = 0;
852 	wake_up(&cl->wait);
853 }
854 
855 
856 /**
857  * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
858  *  host sends disconnect response
859  *
860  * @dev: the device structure.
861  * @disconnect_req: disconnect request bus message from the me
862  *
863  * Return: -ENOMEM on allocation failure
864  */
865 static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
866 		struct hbm_client_connect_request *disconnect_req)
867 {
868 	struct mei_cl *cl;
869 	struct mei_cl_cb *cb;
870 
871 	cl = mei_hbm_cl_find_by_cmd(dev, disconnect_req);
872 	if (cl) {
873 		cl_warn(dev, cl, "fw disconnect request received\n");
874 		cl->state = MEI_FILE_DISCONNECTING;
875 		cl->timer_count = 0;
876 
877 		cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT_RSP,
878 					       NULL);
879 		if (!cb)
880 			return -ENOMEM;
881 	}
882 	return 0;
883 }
884 
885 /**
886  * mei_hbm_pg_enter_res - PG enter response received
887  *
888  * @dev: the device structure.
889  *
890  * Return: 0 on success, -EPROTO on state mismatch
891  */
892 static int mei_hbm_pg_enter_res(struct mei_device *dev)
893 {
894 	if (mei_pg_state(dev) != MEI_PG_OFF ||
895 	    dev->pg_event != MEI_PG_EVENT_WAIT) {
896 		dev_err(dev->dev, "hbm: pg entry response: state mismatch [%s, %d]\n",
897 			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
898 		return -EPROTO;
899 	}
900 
901 	dev->pg_event = MEI_PG_EVENT_RECEIVED;
902 	wake_up(&dev->wait_pg);
903 
904 	return 0;
905 }
906 
907 /**
908  * mei_hbm_pg_resume - process with PG resume
909  *
910  * @dev: the device structure.
911  */
912 void mei_hbm_pg_resume(struct mei_device *dev)
913 {
914 	pm_request_resume(dev->dev);
915 }
916 EXPORT_SYMBOL_GPL(mei_hbm_pg_resume);
917 
918 /**
919  * mei_hbm_pg_exit_res - PG exit response received
920  *
921  * @dev: the device structure.
922  *
923  * Return: 0 on success, -EPROTO on state mismatch
924  */
925 static int mei_hbm_pg_exit_res(struct mei_device *dev)
926 {
927 	if (mei_pg_state(dev) != MEI_PG_ON ||
928 	    (dev->pg_event != MEI_PG_EVENT_WAIT &&
929 	     dev->pg_event != MEI_PG_EVENT_IDLE)) {
930 		dev_err(dev->dev, "hbm: pg exit response: state mismatch [%s, %d]\n",
931 			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
932 		return -EPROTO;
933 	}
934 
935 	switch (dev->pg_event) {
936 	case MEI_PG_EVENT_WAIT:
937 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
938 		wake_up(&dev->wait_pg);
939 		break;
940 	case MEI_PG_EVENT_IDLE:
941 		/*
942 		* If the driver is not waiting on this then
943 		* this is HW initiated exit from PG.
944 		* Start runtime pm resume sequence to exit from PG.
945 		*/
946 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
947 		mei_hbm_pg_resume(dev);
948 		break;
949 	default:
950 		WARN(1, "hbm: pg exit response: unexpected pg event = %d\n",
951 		     dev->pg_event);
952 		return -EPROTO;
953 	}
954 
955 	return 0;
956 }
957 
958 /**
959  * mei_hbm_config_features - check what hbm features and commands
960  *        are supported by the fw
961  *
962  * @dev: the device structure
963  */
964 static void mei_hbm_config_features(struct mei_device *dev)
965 {
966 	/* Power Gating Isolation Support */
967 	dev->hbm_f_pg_supported = 0;
968 	if (dev->version.major_version > HBM_MAJOR_VERSION_PGI)
969 		dev->hbm_f_pg_supported = 1;
970 
971 	if (dev->version.major_version == HBM_MAJOR_VERSION_PGI &&
972 	    dev->version.minor_version >= HBM_MINOR_VERSION_PGI)
973 		dev->hbm_f_pg_supported = 1;
974 
975 	if (dev->version.major_version >= HBM_MAJOR_VERSION_DC)
976 		dev->hbm_f_dc_supported = 1;
977 
978 	if (dev->version.major_version >= HBM_MAJOR_VERSION_IE)
979 		dev->hbm_f_ie_supported = 1;
980 
981 	/* disconnect on connect timeout instead of link reset */
982 	if (dev->version.major_version >= HBM_MAJOR_VERSION_DOT)
983 		dev->hbm_f_dot_supported = 1;
984 
985 	/* Notification Event Support */
986 	if (dev->version.major_version >= HBM_MAJOR_VERSION_EV)
987 		dev->hbm_f_ev_supported = 1;
988 
989 	/* Fixed Address Client Support */
990 	if (dev->version.major_version >= HBM_MAJOR_VERSION_FA)
991 		dev->hbm_f_fa_supported = 1;
992 }
993 
994 /**
995  * mei_hbm_version_is_supported - checks whether the driver can
996  *     support the hbm version of the device
997  *
998  * @dev: the device structure
999  * Return: true if driver can support hbm version of the device
1000  */
1001 bool mei_hbm_version_is_supported(struct mei_device *dev)
1002 {
1003 	return	(dev->version.major_version < HBM_MAJOR_VERSION) ||
1004 		(dev->version.major_version == HBM_MAJOR_VERSION &&
1005 		 dev->version.minor_version <= HBM_MINOR_VERSION);
1006 }
1007 
1008 /**
1009  * mei_hbm_dispatch - bottom half read routine after ISR to
1010  * handle the read bus message cmd processing.
1011  *
1012  * @dev: the device structure
1013  * @hdr: header of bus message
1014  *
1015  * Return: 0 on success and < 0 on failure
1016  */
1017 int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
1018 {
1019 	struct mei_bus_message *mei_msg;
1020 	struct hbm_host_version_response *version_res;
1021 	struct hbm_props_response *props_res;
1022 	struct hbm_host_enum_response *enum_res;
1023 	struct hbm_add_client_request *add_cl_req;
1024 	int ret;
1025 
1026 	struct mei_hbm_cl_cmd *cl_cmd;
1027 	struct hbm_client_connect_request *disconnect_req;
1028 	struct hbm_flow_control *fctrl;
1029 
1030 	/* read the message to our buffer */
1031 	BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
1032 	mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
1033 	mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
1034 	cl_cmd  = (struct mei_hbm_cl_cmd *)mei_msg;
1035 
1036 	/* ignore spurious message and prevent reset nesting
1037 	 * hbm is put to idle during system reset
1038 	 */
1039 	if (dev->hbm_state == MEI_HBM_IDLE) {
1040 		dev_dbg(dev->dev, "hbm: state is idle ignore spurious messages\n");
1041 		return 0;
1042 	}
1043 
1044 	switch (mei_msg->hbm_cmd) {
1045 	case HOST_START_RES_CMD:
1046 		dev_dbg(dev->dev, "hbm: start: response message received.\n");
1047 
1048 		dev->init_clients_timer = 0;
1049 
1050 		version_res = (struct hbm_host_version_response *)mei_msg;
1051 
1052 		dev_dbg(dev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
1053 				HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
1054 				version_res->me_max_version.major_version,
1055 				version_res->me_max_version.minor_version);
1056 
1057 		if (version_res->host_version_supported) {
1058 			dev->version.major_version = HBM_MAJOR_VERSION;
1059 			dev->version.minor_version = HBM_MINOR_VERSION;
1060 		} else {
1061 			dev->version.major_version =
1062 				version_res->me_max_version.major_version;
1063 			dev->version.minor_version =
1064 				version_res->me_max_version.minor_version;
1065 		}
1066 
1067 		if (!mei_hbm_version_is_supported(dev)) {
1068 			dev_warn(dev->dev, "hbm: start: version mismatch - stopping the driver.\n");
1069 
1070 			dev->hbm_state = MEI_HBM_STOPPED;
1071 			if (mei_hbm_stop_req(dev)) {
1072 				dev_err(dev->dev, "hbm: start: failed to send stop request\n");
1073 				return -EIO;
1074 			}
1075 			break;
1076 		}
1077 
1078 		mei_hbm_config_features(dev);
1079 
1080 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1081 		    dev->hbm_state != MEI_HBM_STARTING) {
1082 			dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
1083 				dev->dev_state, dev->hbm_state);
1084 			return -EPROTO;
1085 		}
1086 
1087 		if (mei_hbm_enum_clients_req(dev)) {
1088 			dev_err(dev->dev, "hbm: start: failed to send enumeration request\n");
1089 			return -EIO;
1090 		}
1091 
1092 		wake_up(&dev->wait_hbm_start);
1093 		break;
1094 
1095 	case CLIENT_CONNECT_RES_CMD:
1096 		dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
1097 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
1098 		break;
1099 
1100 	case CLIENT_DISCONNECT_RES_CMD:
1101 		dev_dbg(dev->dev, "hbm: client disconnect response: message received.\n");
1102 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_DISCONNECT);
1103 		break;
1104 
1105 	case MEI_FLOW_CONTROL_CMD:
1106 		dev_dbg(dev->dev, "hbm: client flow control response: message received.\n");
1107 
1108 		fctrl = (struct hbm_flow_control *)mei_msg;
1109 		mei_hbm_cl_tx_flow_ctrl_creds_res(dev, fctrl);
1110 		break;
1111 
1112 	case MEI_PG_ISOLATION_ENTRY_RES_CMD:
1113 		dev_dbg(dev->dev, "hbm: power gate isolation entry response received\n");
1114 		ret = mei_hbm_pg_enter_res(dev);
1115 		if (ret)
1116 			return ret;
1117 		break;
1118 
1119 	case MEI_PG_ISOLATION_EXIT_REQ_CMD:
1120 		dev_dbg(dev->dev, "hbm: power gate isolation exit request received\n");
1121 		ret = mei_hbm_pg_exit_res(dev);
1122 		if (ret)
1123 			return ret;
1124 		break;
1125 
1126 	case HOST_CLIENT_PROPERTIES_RES_CMD:
1127 		dev_dbg(dev->dev, "hbm: properties response: message received.\n");
1128 
1129 		dev->init_clients_timer = 0;
1130 
1131 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1132 		    dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
1133 			dev_err(dev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
1134 				dev->dev_state, dev->hbm_state);
1135 			return -EPROTO;
1136 		}
1137 
1138 		props_res = (struct hbm_props_response *)mei_msg;
1139 
1140 		if (props_res->status) {
1141 			dev_err(dev->dev, "hbm: properties response: wrong status = %d %s\n",
1142 				props_res->status,
1143 				mei_hbm_status_str(props_res->status));
1144 			return -EPROTO;
1145 		}
1146 
1147 		mei_hbm_me_cl_add(dev, props_res);
1148 
1149 		/* request property for the next client */
1150 		if (mei_hbm_prop_req(dev, props_res->me_addr + 1))
1151 			return -EIO;
1152 
1153 		break;
1154 
1155 	case HOST_ENUM_RES_CMD:
1156 		dev_dbg(dev->dev, "hbm: enumeration response: message received\n");
1157 
1158 		dev->init_clients_timer = 0;
1159 
1160 		enum_res = (struct hbm_host_enum_response *) mei_msg;
1161 		BUILD_BUG_ON(sizeof(dev->me_clients_map)
1162 				< sizeof(enum_res->valid_addresses));
1163 		memcpy(dev->me_clients_map, enum_res->valid_addresses,
1164 				sizeof(enum_res->valid_addresses));
1165 
1166 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1167 		    dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
1168 			dev_err(dev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
1169 				dev->dev_state, dev->hbm_state);
1170 			return -EPROTO;
1171 		}
1172 
1173 		dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
1174 
1175 		/* first property request */
1176 		if (mei_hbm_prop_req(dev, 0))
1177 			return -EIO;
1178 
1179 		break;
1180 
1181 	case HOST_STOP_RES_CMD:
1182 		dev_dbg(dev->dev, "hbm: stop response: message received\n");
1183 
1184 		dev->init_clients_timer = 0;
1185 
1186 		if (dev->hbm_state != MEI_HBM_STOPPED) {
1187 			dev_err(dev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
1188 				dev->dev_state, dev->hbm_state);
1189 			return -EPROTO;
1190 		}
1191 
1192 		dev->dev_state = MEI_DEV_POWER_DOWN;
1193 		dev_info(dev->dev, "hbm: stop response: resetting.\n");
1194 		/* force the reset */
1195 		return -EPROTO;
1196 		break;
1197 
1198 	case CLIENT_DISCONNECT_REQ_CMD:
1199 		dev_dbg(dev->dev, "hbm: disconnect request: message received\n");
1200 
1201 		disconnect_req = (struct hbm_client_connect_request *)mei_msg;
1202 		mei_hbm_fw_disconnect_req(dev, disconnect_req);
1203 		break;
1204 
1205 	case ME_STOP_REQ_CMD:
1206 		dev_dbg(dev->dev, "hbm: stop request: message received\n");
1207 		dev->hbm_state = MEI_HBM_STOPPED;
1208 		if (mei_hbm_stop_req(dev)) {
1209 			dev_err(dev->dev, "hbm: stop request: failed to send stop request\n");
1210 			return -EIO;
1211 		}
1212 		break;
1213 
1214 	case MEI_HBM_ADD_CLIENT_REQ_CMD:
1215 		dev_dbg(dev->dev, "hbm: add client request received\n");
1216 		/*
1217 		 * after the host receives the enum_resp
1218 		 * message clients may be added or removed
1219 		 */
1220 		if (dev->hbm_state <= MEI_HBM_ENUM_CLIENTS ||
1221 		    dev->hbm_state >= MEI_HBM_STOPPED) {
1222 			dev_err(dev->dev, "hbm: add client: state mismatch, [%d, %d]\n",
1223 				dev->dev_state, dev->hbm_state);
1224 			return -EPROTO;
1225 		}
1226 		add_cl_req = (struct hbm_add_client_request *)mei_msg;
1227 		ret = mei_hbm_fw_add_cl_req(dev, add_cl_req);
1228 		if (ret) {
1229 			dev_err(dev->dev, "hbm: add client: failed to send response %d\n",
1230 				ret);
1231 			return -EIO;
1232 		}
1233 		dev_dbg(dev->dev, "hbm: add client request processed\n");
1234 		break;
1235 
1236 	case MEI_HBM_NOTIFY_RES_CMD:
1237 		dev_dbg(dev->dev, "hbm: notify response received\n");
1238 		mei_hbm_cl_res(dev, cl_cmd, notify_res_to_fop(cl_cmd));
1239 		break;
1240 
1241 	case MEI_HBM_NOTIFICATION_CMD:
1242 		dev_dbg(dev->dev, "hbm: notification\n");
1243 		mei_hbm_cl_notify(dev, cl_cmd);
1244 		break;
1245 
1246 	default:
1247 		BUG();
1248 		break;
1249 
1250 	}
1251 	return 0;
1252 }
1253 
1254