xref: /freebsd/sys/dev/e1000/e1000_mbx.c (revision a7623790fb345e6dc986dfd31df0ace115e6f2e4)
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3 
4   Copyright (c) 2001-2015, Intel Corporation
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33 ******************************************************************************/
34 /*$FreeBSD$*/
35 
36 #include "e1000_mbx.h"
37 
38 /**
39  *  e1000_null_mbx_check_for_flag - No-op function, return 0
40  *  @hw: pointer to the HW structure
41  **/
42 static s32 e1000_null_mbx_check_for_flag(struct e1000_hw E1000_UNUSEDARG *hw,
43 					 u16 E1000_UNUSEDARG mbx_id)
44 {
45 	DEBUGFUNC("e1000_null_mbx_check_flag");
46 
47 	return E1000_SUCCESS;
48 }
49 
50 /**
51  *  e1000_null_mbx_transact - No-op function, return 0
52  *  @hw: pointer to the HW structure
53  **/
54 static s32 e1000_null_mbx_transact(struct e1000_hw E1000_UNUSEDARG *hw,
55 				   u32 E1000_UNUSEDARG *msg,
56 				   u16 E1000_UNUSEDARG size,
57 				   u16 E1000_UNUSEDARG mbx_id)
58 {
59 	DEBUGFUNC("e1000_null_mbx_rw_msg");
60 
61 	return E1000_SUCCESS;
62 }
63 
64 /**
65  *  e1000_read_mbx - Reads a message from the mailbox
66  *  @hw: pointer to the HW structure
67  *  @msg: The message buffer
68  *  @size: Length of buffer
69  *  @mbx_id: id of mailbox to read
70  *
71  *  returns SUCCESS if it successfully read message from buffer
72  **/
73 s32 e1000_read_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
74 {
75 	struct e1000_mbx_info *mbx = &hw->mbx;
76 	s32 ret_val = -E1000_ERR_MBX;
77 
78 	DEBUGFUNC("e1000_read_mbx");
79 
80 	/* limit read to size of mailbox */
81 	if (size > mbx->size)
82 		size = mbx->size;
83 
84 	if (mbx->ops.read)
85 		ret_val = mbx->ops.read(hw, msg, size, mbx_id);
86 
87 	return ret_val;
88 }
89 
90 /**
91  *  e1000_write_mbx - Write a message to the mailbox
92  *  @hw: pointer to the HW structure
93  *  @msg: The message buffer
94  *  @size: Length of buffer
95  *  @mbx_id: id of mailbox to write
96  *
97  *  returns SUCCESS if it successfully copied message into the buffer
98  **/
99 s32 e1000_write_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
100 {
101 	struct e1000_mbx_info *mbx = &hw->mbx;
102 	s32 ret_val = E1000_SUCCESS;
103 
104 	DEBUGFUNC("e1000_write_mbx");
105 
106 	if (size > mbx->size)
107 		ret_val = -E1000_ERR_MBX;
108 
109 	else if (mbx->ops.write)
110 		ret_val = mbx->ops.write(hw, msg, size, mbx_id);
111 
112 	return ret_val;
113 }
114 
115 /**
116  *  e1000_check_for_msg - checks to see if someone sent us mail
117  *  @hw: pointer to the HW structure
118  *  @mbx_id: id of mailbox to check
119  *
120  *  returns SUCCESS if the Status bit was found or else ERR_MBX
121  **/
122 s32 e1000_check_for_msg(struct e1000_hw *hw, u16 mbx_id)
123 {
124 	struct e1000_mbx_info *mbx = &hw->mbx;
125 	s32 ret_val = -E1000_ERR_MBX;
126 
127 	DEBUGFUNC("e1000_check_for_msg");
128 
129 	if (mbx->ops.check_for_msg)
130 		ret_val = mbx->ops.check_for_msg(hw, mbx_id);
131 
132 	return ret_val;
133 }
134 
135 /**
136  *  e1000_check_for_ack - checks to see if someone sent us ACK
137  *  @hw: pointer to the HW structure
138  *  @mbx_id: id of mailbox to check
139  *
140  *  returns SUCCESS if the Status bit was found or else ERR_MBX
141  **/
142 s32 e1000_check_for_ack(struct e1000_hw *hw, u16 mbx_id)
143 {
144 	struct e1000_mbx_info *mbx = &hw->mbx;
145 	s32 ret_val = -E1000_ERR_MBX;
146 
147 	DEBUGFUNC("e1000_check_for_ack");
148 
149 	if (mbx->ops.check_for_ack)
150 		ret_val = mbx->ops.check_for_ack(hw, mbx_id);
151 
152 	return ret_val;
153 }
154 
155 /**
156  *  e1000_check_for_rst - checks to see if other side has reset
157  *  @hw: pointer to the HW structure
158  *  @mbx_id: id of mailbox to check
159  *
160  *  returns SUCCESS if the Status bit was found or else ERR_MBX
161  **/
162 s32 e1000_check_for_rst(struct e1000_hw *hw, u16 mbx_id)
163 {
164 	struct e1000_mbx_info *mbx = &hw->mbx;
165 	s32 ret_val = -E1000_ERR_MBX;
166 
167 	DEBUGFUNC("e1000_check_for_rst");
168 
169 	if (mbx->ops.check_for_rst)
170 		ret_val = mbx->ops.check_for_rst(hw, mbx_id);
171 
172 	return ret_val;
173 }
174 
175 /**
176  *  e1000_poll_for_msg - Wait for message notification
177  *  @hw: pointer to the HW structure
178  *  @mbx_id: id of mailbox to write
179  *
180  *  returns SUCCESS if it successfully received a message notification
181  **/
182 static s32 e1000_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
183 {
184 	struct e1000_mbx_info *mbx = &hw->mbx;
185 	int countdown = mbx->timeout;
186 
187 	DEBUGFUNC("e1000_poll_for_msg");
188 
189 	if (!countdown || !mbx->ops.check_for_msg)
190 		goto out;
191 
192 	while (countdown && mbx->ops.check_for_msg(hw, mbx_id)) {
193 		countdown--;
194 		if (!countdown)
195 			break;
196 		usec_delay(mbx->usec_delay);
197 	}
198 
199 	/* if we failed, all future posted messages fail until reset */
200 	if (!countdown)
201 		mbx->timeout = 0;
202 out:
203 	return countdown ? E1000_SUCCESS : -E1000_ERR_MBX;
204 }
205 
206 /**
207  *  e1000_poll_for_ack - Wait for message acknowledgement
208  *  @hw: pointer to the HW structure
209  *  @mbx_id: id of mailbox to write
210  *
211  *  returns SUCCESS if it successfully received a message acknowledgement
212  **/
213 static s32 e1000_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
214 {
215 	struct e1000_mbx_info *mbx = &hw->mbx;
216 	int countdown = mbx->timeout;
217 
218 	DEBUGFUNC("e1000_poll_for_ack");
219 
220 	if (!countdown || !mbx->ops.check_for_ack)
221 		goto out;
222 
223 	while (countdown && mbx->ops.check_for_ack(hw, mbx_id)) {
224 		countdown--;
225 		if (!countdown)
226 			break;
227 		usec_delay(mbx->usec_delay);
228 	}
229 
230 	/* if we failed, all future posted messages fail until reset */
231 	if (!countdown)
232 		mbx->timeout = 0;
233 out:
234 	return countdown ? E1000_SUCCESS : -E1000_ERR_MBX;
235 }
236 
237 /**
238  *  e1000_read_posted_mbx - Wait for message notification and receive message
239  *  @hw: pointer to the HW structure
240  *  @msg: The message buffer
241  *  @size: Length of buffer
242  *  @mbx_id: id of mailbox to write
243  *
244  *  returns SUCCESS if it successfully received a message notification and
245  *  copied it into the receive buffer.
246  **/
247 s32 e1000_read_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
248 {
249 	struct e1000_mbx_info *mbx = &hw->mbx;
250 	s32 ret_val = -E1000_ERR_MBX;
251 
252 	DEBUGFUNC("e1000_read_posted_mbx");
253 
254 	if (!mbx->ops.read)
255 		goto out;
256 
257 	ret_val = e1000_poll_for_msg(hw, mbx_id);
258 
259 	/* if ack received read message, otherwise we timed out */
260 	if (!ret_val)
261 		ret_val = mbx->ops.read(hw, msg, size, mbx_id);
262 out:
263 	return ret_val;
264 }
265 
266 /**
267  *  e1000_write_posted_mbx - Write a message to the mailbox, wait for ack
268  *  @hw: pointer to the HW structure
269  *  @msg: The message buffer
270  *  @size: Length of buffer
271  *  @mbx_id: id of mailbox to write
272  *
273  *  returns SUCCESS if it successfully copied message into the buffer and
274  *  received an ack to that message within delay * timeout period
275  **/
276 s32 e1000_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
277 {
278 	struct e1000_mbx_info *mbx = &hw->mbx;
279 	s32 ret_val = -E1000_ERR_MBX;
280 
281 	DEBUGFUNC("e1000_write_posted_mbx");
282 
283 	/* exit if either we can't write or there isn't a defined timeout */
284 	if (!mbx->ops.write || !mbx->timeout)
285 		goto out;
286 
287 	/* send msg */
288 	ret_val = mbx->ops.write(hw, msg, size, mbx_id);
289 
290 	/* if msg sent wait until we receive an ack */
291 	if (!ret_val)
292 		ret_val = e1000_poll_for_ack(hw, mbx_id);
293 out:
294 	return ret_val;
295 }
296 
297 /**
298  *  e1000_init_mbx_ops_generic - Initialize mbx function pointers
299  *  @hw: pointer to the HW structure
300  *
301  *  Sets the function pointers to no-op functions
302  **/
303 void e1000_init_mbx_ops_generic(struct e1000_hw *hw)
304 {
305 	struct e1000_mbx_info *mbx = &hw->mbx;
306 	mbx->ops.init_params = e1000_null_ops_generic;
307 	mbx->ops.read = e1000_null_mbx_transact;
308 	mbx->ops.write = e1000_null_mbx_transact;
309 	mbx->ops.check_for_msg = e1000_null_mbx_check_for_flag;
310 	mbx->ops.check_for_ack = e1000_null_mbx_check_for_flag;
311 	mbx->ops.check_for_rst = e1000_null_mbx_check_for_flag;
312 	mbx->ops.read_posted = e1000_read_posted_mbx;
313 	mbx->ops.write_posted = e1000_write_posted_mbx;
314 }
315 
316 /**
317  *  e1000_read_v2p_mailbox - read v2p mailbox
318  *  @hw: pointer to the HW structure
319  *
320  *  This function is used to read the v2p mailbox without losing the read to
321  *  clear status bits.
322  **/
323 static u32 e1000_read_v2p_mailbox(struct e1000_hw *hw)
324 {
325 	u32 v2p_mailbox = E1000_READ_REG(hw, E1000_V2PMAILBOX(0));
326 
327 	v2p_mailbox |= hw->dev_spec.vf.v2p_mailbox;
328 	hw->dev_spec.vf.v2p_mailbox |= v2p_mailbox & E1000_V2PMAILBOX_R2C_BITS;
329 
330 	return v2p_mailbox;
331 }
332 
333 /**
334  *  e1000_check_for_bit_vf - Determine if a status bit was set
335  *  @hw: pointer to the HW structure
336  *  @mask: bitmask for bits to be tested and cleared
337  *
338  *  This function is used to check for the read to clear bits within
339  *  the V2P mailbox.
340  **/
341 static s32 e1000_check_for_bit_vf(struct e1000_hw *hw, u32 mask)
342 {
343 	u32 v2p_mailbox = e1000_read_v2p_mailbox(hw);
344 	s32 ret_val = -E1000_ERR_MBX;
345 
346 	if (v2p_mailbox & mask)
347 		ret_val = E1000_SUCCESS;
348 
349 	hw->dev_spec.vf.v2p_mailbox &= ~mask;
350 
351 	return ret_val;
352 }
353 
354 /**
355  *  e1000_check_for_msg_vf - checks to see if the PF has sent mail
356  *  @hw: pointer to the HW structure
357  *  @mbx_id: id of mailbox to check
358  *
359  *  returns SUCCESS if the PF has set the Status bit or else ERR_MBX
360  **/
361 static s32 e1000_check_for_msg_vf(struct e1000_hw *hw,
362 				  u16 E1000_UNUSEDARG mbx_id)
363 {
364 	s32 ret_val = -E1000_ERR_MBX;
365 
366 	DEBUGFUNC("e1000_check_for_msg_vf");
367 
368 	if (!e1000_check_for_bit_vf(hw, E1000_V2PMAILBOX_PFSTS)) {
369 		ret_val = E1000_SUCCESS;
370 		hw->mbx.stats.reqs++;
371 	}
372 
373 	return ret_val;
374 }
375 
376 /**
377  *  e1000_check_for_ack_vf - checks to see if the PF has ACK'd
378  *  @hw: pointer to the HW structure
379  *  @mbx_id: id of mailbox to check
380  *
381  *  returns SUCCESS if the PF has set the ACK bit or else ERR_MBX
382  **/
383 static s32 e1000_check_for_ack_vf(struct e1000_hw *hw,
384 				  u16 E1000_UNUSEDARG mbx_id)
385 {
386 	s32 ret_val = -E1000_ERR_MBX;
387 
388 	DEBUGFUNC("e1000_check_for_ack_vf");
389 
390 	if (!e1000_check_for_bit_vf(hw, E1000_V2PMAILBOX_PFACK)) {
391 		ret_val = E1000_SUCCESS;
392 		hw->mbx.stats.acks++;
393 	}
394 
395 	return ret_val;
396 }
397 
398 /**
399  *  e1000_check_for_rst_vf - checks to see if the PF has reset
400  *  @hw: pointer to the HW structure
401  *  @mbx_id: id of mailbox to check
402  *
403  *  returns TRUE if the PF has set the reset done bit or else FALSE
404  **/
405 static s32 e1000_check_for_rst_vf(struct e1000_hw *hw,
406 				  u16 E1000_UNUSEDARG mbx_id)
407 {
408 	s32 ret_val = -E1000_ERR_MBX;
409 
410 	DEBUGFUNC("e1000_check_for_rst_vf");
411 
412 	if (!e1000_check_for_bit_vf(hw, (E1000_V2PMAILBOX_RSTD |
413 					 E1000_V2PMAILBOX_RSTI))) {
414 		ret_val = E1000_SUCCESS;
415 		hw->mbx.stats.rsts++;
416 	}
417 
418 	return ret_val;
419 }
420 
421 /**
422  *  e1000_obtain_mbx_lock_vf - obtain mailbox lock
423  *  @hw: pointer to the HW structure
424  *
425  *  return SUCCESS if we obtained the mailbox lock
426  **/
427 static s32 e1000_obtain_mbx_lock_vf(struct e1000_hw *hw)
428 {
429 	s32 ret_val = -E1000_ERR_MBX;
430 	int count = 10;
431 
432 	DEBUGFUNC("e1000_obtain_mbx_lock_vf");
433 
434 	do {
435 		/* Take ownership of the buffer */
436 		E1000_WRITE_REG(hw, E1000_V2PMAILBOX(0), E1000_V2PMAILBOX_VFU);
437 
438 		/* reserve mailbox for vf use */
439 		if (e1000_read_v2p_mailbox(hw) & E1000_V2PMAILBOX_VFU) {
440 			ret_val = E1000_SUCCESS;
441 			break;
442 		}
443 		usec_delay(1000);
444 	} while (count-- > 0);
445 
446 	return ret_val;
447 }
448 
449 /**
450  *  e1000_write_mbx_vf - Write a message to the mailbox
451  *  @hw: pointer to the HW structure
452  *  @msg: The message buffer
453  *  @size: Length of buffer
454  *  @mbx_id: id of mailbox to write
455  *
456  *  returns SUCCESS if it successfully copied message into the buffer
457  **/
458 static s32 e1000_write_mbx_vf(struct e1000_hw *hw, u32 *msg, u16 size,
459 			      u16 E1000_UNUSEDARG mbx_id)
460 {
461 	s32 ret_val;
462 	u16 i;
463 
464 
465 	DEBUGFUNC("e1000_write_mbx_vf");
466 
467 	/* lock the mailbox to prevent pf/vf race condition */
468 	ret_val = e1000_obtain_mbx_lock_vf(hw);
469 	if (ret_val)
470 		goto out_no_write;
471 
472 	/* flush msg and acks as we are overwriting the message buffer */
473 	e1000_check_for_msg_vf(hw, 0);
474 	e1000_check_for_ack_vf(hw, 0);
475 
476 	/* copy the caller specified message to the mailbox memory buffer */
477 	for (i = 0; i < size; i++)
478 		E1000_WRITE_REG_ARRAY(hw, E1000_VMBMEM(0), i, msg[i]);
479 
480 	/* update stats */
481 	hw->mbx.stats.msgs_tx++;
482 
483 	/* Drop VFU and interrupt the PF to tell it a message has been sent */
484 	E1000_WRITE_REG(hw, E1000_V2PMAILBOX(0), E1000_V2PMAILBOX_REQ);
485 
486 out_no_write:
487 	return ret_val;
488 }
489 
490 /**
491  *  e1000_read_mbx_vf - Reads a message from the inbox intended for vf
492  *  @hw: pointer to the HW structure
493  *  @msg: The message buffer
494  *  @size: Length of buffer
495  *  @mbx_id: id of mailbox to read
496  *
497  *  returns SUCCESS if it successfully read message from buffer
498  **/
499 static s32 e1000_read_mbx_vf(struct e1000_hw *hw, u32 *msg, u16 size,
500 			     u16 E1000_UNUSEDARG mbx_id)
501 {
502 	s32 ret_val = E1000_SUCCESS;
503 	u16 i;
504 
505 	DEBUGFUNC("e1000_read_mbx_vf");
506 
507 	/* lock the mailbox to prevent pf/vf race condition */
508 	ret_val = e1000_obtain_mbx_lock_vf(hw);
509 	if (ret_val)
510 		goto out_no_read;
511 
512 	/* copy the message from the mailbox memory buffer */
513 	for (i = 0; i < size; i++)
514 		msg[i] = E1000_READ_REG_ARRAY(hw, E1000_VMBMEM(0), i);
515 
516 	/* Acknowledge receipt and release mailbox, then we're done */
517 	E1000_WRITE_REG(hw, E1000_V2PMAILBOX(0), E1000_V2PMAILBOX_ACK);
518 
519 	/* update stats */
520 	hw->mbx.stats.msgs_rx++;
521 
522 out_no_read:
523 	return ret_val;
524 }
525 
526 /**
527  *  e1000_init_mbx_params_vf - set initial values for vf mailbox
528  *  @hw: pointer to the HW structure
529  *
530  *  Initializes the hw->mbx struct to correct values for vf mailbox
531  */
532 s32 e1000_init_mbx_params_vf(struct e1000_hw *hw)
533 {
534 	struct e1000_mbx_info *mbx = &hw->mbx;
535 
536 	/* start mailbox as timed out and let the reset_hw call set the timeout
537 	 * value to begin communications */
538 	mbx->timeout = 0;
539 	mbx->usec_delay = E1000_VF_MBX_INIT_DELAY;
540 
541 	mbx->size = E1000_VFMAILBOX_SIZE;
542 
543 	mbx->ops.read = e1000_read_mbx_vf;
544 	mbx->ops.write = e1000_write_mbx_vf;
545 	mbx->ops.read_posted = e1000_read_posted_mbx;
546 	mbx->ops.write_posted = e1000_write_posted_mbx;
547 	mbx->ops.check_for_msg = e1000_check_for_msg_vf;
548 	mbx->ops.check_for_ack = e1000_check_for_ack_vf;
549 	mbx->ops.check_for_rst = e1000_check_for_rst_vf;
550 
551 	mbx->stats.msgs_tx = 0;
552 	mbx->stats.msgs_rx = 0;
553 	mbx->stats.reqs = 0;
554 	mbx->stats.acks = 0;
555 	mbx->stats.rsts = 0;
556 
557 	return E1000_SUCCESS;
558 }
559 
560 static s32 e1000_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
561 {
562 	u32 mbvficr = E1000_READ_REG(hw, E1000_MBVFICR);
563 	s32 ret_val = -E1000_ERR_MBX;
564 
565 	if (mbvficr & mask) {
566 		ret_val = E1000_SUCCESS;
567 		E1000_WRITE_REG(hw, E1000_MBVFICR, mask);
568 	}
569 
570 	return ret_val;
571 }
572 
573 /**
574  *  e1000_check_for_msg_pf - checks to see if the VF has sent mail
575  *  @hw: pointer to the HW structure
576  *  @vf_number: the VF index
577  *
578  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
579  **/
580 static s32 e1000_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
581 {
582 	s32 ret_val = -E1000_ERR_MBX;
583 
584 	DEBUGFUNC("e1000_check_for_msg_pf");
585 
586 	if (!e1000_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
587 		ret_val = E1000_SUCCESS;
588 		hw->mbx.stats.reqs++;
589 	}
590 
591 	return ret_val;
592 }
593 
594 /**
595  *  e1000_check_for_ack_pf - checks to see if the VF has ACKed
596  *  @hw: pointer to the HW structure
597  *  @vf_number: the VF index
598  *
599  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
600  **/
601 static s32 e1000_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
602 {
603 	s32 ret_val = -E1000_ERR_MBX;
604 
605 	DEBUGFUNC("e1000_check_for_ack_pf");
606 
607 	if (!e1000_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
608 		ret_val = E1000_SUCCESS;
609 		hw->mbx.stats.acks++;
610 	}
611 
612 	return ret_val;
613 }
614 
615 /**
616  *  e1000_check_for_rst_pf - checks to see if the VF has reset
617  *  @hw: pointer to the HW structure
618  *  @vf_number: the VF index
619  *
620  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
621  **/
622 static s32 e1000_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
623 {
624 	u32 vflre = E1000_READ_REG(hw, E1000_VFLRE);
625 	s32 ret_val = -E1000_ERR_MBX;
626 
627 	DEBUGFUNC("e1000_check_for_rst_pf");
628 
629 	if (vflre & (1 << vf_number)) {
630 		ret_val = E1000_SUCCESS;
631 		E1000_WRITE_REG(hw, E1000_VFLRE, (1 << vf_number));
632 		hw->mbx.stats.rsts++;
633 	}
634 
635 	return ret_val;
636 }
637 
638 /**
639  *  e1000_obtain_mbx_lock_pf - obtain mailbox lock
640  *  @hw: pointer to the HW structure
641  *  @vf_number: the VF index
642  *
643  *  return SUCCESS if we obtained the mailbox lock
644  **/
645 static s32 e1000_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
646 {
647 	s32 ret_val = -E1000_ERR_MBX;
648 	u32 p2v_mailbox;
649 	int count = 10;
650 
651 	DEBUGFUNC("e1000_obtain_mbx_lock_pf");
652 
653 	do {
654 		/* Take ownership of the buffer */
655 		E1000_WRITE_REG(hw, E1000_P2VMAILBOX(vf_number),
656 				E1000_P2VMAILBOX_PFU);
657 
658 		/* reserve mailbox for pf use */
659 		p2v_mailbox = E1000_READ_REG(hw, E1000_P2VMAILBOX(vf_number));
660 		if (p2v_mailbox & E1000_P2VMAILBOX_PFU) {
661 			ret_val = E1000_SUCCESS;
662 			break;
663 		}
664 		usec_delay(1000);
665 	} while (count-- > 0);
666 
667 	return ret_val;
668 
669 }
670 
671 /**
672  *  e1000_write_mbx_pf - Places a message in the mailbox
673  *  @hw: pointer to the HW structure
674  *  @msg: The message buffer
675  *  @size: Length of buffer
676  *  @vf_number: the VF index
677  *
678  *  returns SUCCESS if it successfully copied message into the buffer
679  **/
680 static s32 e1000_write_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
681 			      u16 vf_number)
682 {
683 	s32 ret_val;
684 	u16 i;
685 
686 	DEBUGFUNC("e1000_write_mbx_pf");
687 
688 	/* lock the mailbox to prevent pf/vf race condition */
689 	ret_val = e1000_obtain_mbx_lock_pf(hw, vf_number);
690 	if (ret_val)
691 		goto out_no_write;
692 
693 	/* flush msg and acks as we are overwriting the message buffer */
694 	e1000_check_for_msg_pf(hw, vf_number);
695 	e1000_check_for_ack_pf(hw, vf_number);
696 
697 	/* copy the caller specified message to the mailbox memory buffer */
698 	for (i = 0; i < size; i++)
699 		E1000_WRITE_REG_ARRAY(hw, E1000_VMBMEM(vf_number), i, msg[i]);
700 
701 	/* Interrupt VF to tell it a message has been sent and release buffer*/
702 	E1000_WRITE_REG(hw, E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_STS);
703 
704 	/* update stats */
705 	hw->mbx.stats.msgs_tx++;
706 
707 out_no_write:
708 	return ret_val;
709 
710 }
711 
712 /**
713  *  e1000_read_mbx_pf - Read a message from the mailbox
714  *  @hw: pointer to the HW structure
715  *  @msg: The message buffer
716  *  @size: Length of buffer
717  *  @vf_number: the VF index
718  *
719  *  This function copies a message from the mailbox buffer to the caller's
720  *  memory buffer.  The presumption is that the caller knows that there was
721  *  a message due to a VF request so no polling for message is needed.
722  **/
723 static s32 e1000_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
724 			     u16 vf_number)
725 {
726 	s32 ret_val;
727 	u16 i;
728 
729 	DEBUGFUNC("e1000_read_mbx_pf");
730 
731 	/* lock the mailbox to prevent pf/vf race condition */
732 	ret_val = e1000_obtain_mbx_lock_pf(hw, vf_number);
733 	if (ret_val)
734 		goto out_no_read;
735 
736 	/* copy the message to the mailbox memory buffer */
737 	for (i = 0; i < size; i++)
738 		msg[i] = E1000_READ_REG_ARRAY(hw, E1000_VMBMEM(vf_number), i);
739 
740 	/* Acknowledge the message and release buffer */
741 	E1000_WRITE_REG(hw, E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_ACK);
742 
743 	/* update stats */
744 	hw->mbx.stats.msgs_rx++;
745 
746 out_no_read:
747 	return ret_val;
748 }
749 
750 /**
751  *  e1000_init_mbx_params_pf - set initial values for pf mailbox
752  *  @hw: pointer to the HW structure
753  *
754  *  Initializes the hw->mbx struct to correct values for pf mailbox
755  */
756 s32 e1000_init_mbx_params_pf(struct e1000_hw *hw)
757 {
758 	struct e1000_mbx_info *mbx = &hw->mbx;
759 
760 	switch (hw->mac.type) {
761 	case e1000_82576:
762 	case e1000_i350:
763 	case e1000_i354:
764 		mbx->timeout = 0;
765 		mbx->usec_delay = 0;
766 
767 		mbx->size = E1000_VFMAILBOX_SIZE;
768 
769 		mbx->ops.read = e1000_read_mbx_pf;
770 		mbx->ops.write = e1000_write_mbx_pf;
771 		mbx->ops.read_posted = e1000_read_posted_mbx;
772 		mbx->ops.write_posted = e1000_write_posted_mbx;
773 		mbx->ops.check_for_msg = e1000_check_for_msg_pf;
774 		mbx->ops.check_for_ack = e1000_check_for_ack_pf;
775 		mbx->ops.check_for_rst = e1000_check_for_rst_pf;
776 
777 		mbx->stats.msgs_tx = 0;
778 		mbx->stats.msgs_rx = 0;
779 		mbx->stats.reqs = 0;
780 		mbx->stats.acks = 0;
781 		mbx->stats.rsts = 0;
782 		/* FALLTHROUGH */
783 	default:
784 		return E1000_SUCCESS;
785 	}
786 }
787 
788