xref: /freebsd/sys/dev/e1000/e1000_mbx.c (revision 59c8e88e72633afbc47a4ace0d2170d00d51f7dc)
1 /******************************************************************************
2   SPDX-License-Identifier: BSD-3-Clause
3 
4   Copyright (c) 2001-2020, Intel Corporation
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33 ******************************************************************************/
34 
35 #include "e1000_mbx.h"
36 
37 /**
38  *  e1000_null_mbx_check_for_flag - No-op function, return 0
39  *  @hw: pointer to the HW structure
40  *  @mbx_id: id of mailbox to read
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  *  @msg: The message buffer
54  *  @size: Length of buffer
55  *  @mbx_id: id of mailbox to read
56  **/
57 static s32 e1000_null_mbx_transact(struct e1000_hw E1000_UNUSEDARG *hw,
58 				   u32 E1000_UNUSEDARG *msg,
59 				   u16 E1000_UNUSEDARG size,
60 				   u16 E1000_UNUSEDARG mbx_id)
61 {
62 	DEBUGFUNC("e1000_null_mbx_rw_msg");
63 
64 	return E1000_SUCCESS;
65 }
66 
67 /**
68  *  e1000_read_mbx - Reads a message from the mailbox
69  *  @hw: pointer to the HW structure
70  *  @msg: The message buffer
71  *  @size: Length of buffer
72  *  @mbx_id: id of mailbox to read
73  *
74  *  returns SUCCESS if it successfully read message from buffer
75  **/
76 s32 e1000_read_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
77 {
78 	struct e1000_mbx_info *mbx = &hw->mbx;
79 	s32 ret_val = -E1000_ERR_MBX;
80 
81 	DEBUGFUNC("e1000_read_mbx");
82 
83 	/* limit read to size of mailbox */
84 	if (size > mbx->size)
85 		size = mbx->size;
86 
87 	if (mbx->ops.read)
88 		ret_val = mbx->ops.read(hw, msg, size, mbx_id);
89 
90 	return ret_val;
91 }
92 
93 /**
94  *  e1000_write_mbx - Write a message to the mailbox
95  *  @hw: pointer to the HW structure
96  *  @msg: The message buffer
97  *  @size: Length of buffer
98  *  @mbx_id: id of mailbox to write
99  *
100  *  returns SUCCESS if it successfully copied message into the buffer
101  **/
102 s32 e1000_write_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
103 {
104 	struct e1000_mbx_info *mbx = &hw->mbx;
105 	s32 ret_val = E1000_SUCCESS;
106 
107 	DEBUGFUNC("e1000_write_mbx");
108 
109 	if (size > mbx->size)
110 		ret_val = -E1000_ERR_MBX;
111 
112 	else if (mbx->ops.write)
113 		ret_val = mbx->ops.write(hw, msg, size, mbx_id);
114 
115 	return ret_val;
116 }
117 
118 /**
119  *  e1000_check_for_msg - checks to see if someone sent us mail
120  *  @hw: pointer to the HW structure
121  *  @mbx_id: id of mailbox to check
122  *
123  *  returns SUCCESS if the Status bit was found or else ERR_MBX
124  **/
125 s32 e1000_check_for_msg(struct e1000_hw *hw, u16 mbx_id)
126 {
127 	struct e1000_mbx_info *mbx = &hw->mbx;
128 	s32 ret_val = -E1000_ERR_MBX;
129 
130 	DEBUGFUNC("e1000_check_for_msg");
131 
132 	if (mbx->ops.check_for_msg)
133 		ret_val = mbx->ops.check_for_msg(hw, mbx_id);
134 
135 	return ret_val;
136 }
137 
138 /**
139  *  e1000_check_for_ack - checks to see if someone sent us ACK
140  *  @hw: pointer to the HW structure
141  *  @mbx_id: id of mailbox to check
142  *
143  *  returns SUCCESS if the Status bit was found or else ERR_MBX
144  **/
145 s32 e1000_check_for_ack(struct e1000_hw *hw, u16 mbx_id)
146 {
147 	struct e1000_mbx_info *mbx = &hw->mbx;
148 	s32 ret_val = -E1000_ERR_MBX;
149 
150 	DEBUGFUNC("e1000_check_for_ack");
151 
152 	if (mbx->ops.check_for_ack)
153 		ret_val = mbx->ops.check_for_ack(hw, mbx_id);
154 
155 	return ret_val;
156 }
157 
158 /**
159  *  e1000_check_for_rst - checks to see if other side has reset
160  *  @hw: pointer to the HW structure
161  *  @mbx_id: id of mailbox to check
162  *
163  *  returns SUCCESS if the Status bit was found or else ERR_MBX
164  **/
165 s32 e1000_check_for_rst(struct e1000_hw *hw, u16 mbx_id)
166 {
167 	struct e1000_mbx_info *mbx = &hw->mbx;
168 	s32 ret_val = -E1000_ERR_MBX;
169 
170 	DEBUGFUNC("e1000_check_for_rst");
171 
172 	if (mbx->ops.check_for_rst)
173 		ret_val = mbx->ops.check_for_rst(hw, mbx_id);
174 
175 	return ret_val;
176 }
177 
178 /**
179  *  e1000_poll_for_msg - Wait for message notification
180  *  @hw: pointer to the HW structure
181  *  @mbx_id: id of mailbox to write
182  *
183  *  returns SUCCESS if it successfully received a message notification
184  **/
185 static s32 e1000_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
186 {
187 	struct e1000_mbx_info *mbx = &hw->mbx;
188 	int countdown = mbx->timeout;
189 
190 	DEBUGFUNC("e1000_poll_for_msg");
191 
192 	if (!countdown || !mbx->ops.check_for_msg)
193 		goto out;
194 
195 	while (countdown && mbx->ops.check_for_msg(hw, mbx_id)) {
196 		countdown--;
197 		if (!countdown)
198 			break;
199 		usec_delay(mbx->usec_delay);
200 	}
201 
202 	/* if we failed, all future posted messages fail until reset */
203 	if (!countdown)
204 		mbx->timeout = 0;
205 out:
206 	return countdown ? E1000_SUCCESS : -E1000_ERR_MBX;
207 }
208 
209 /**
210  *  e1000_poll_for_ack - Wait for message acknowledgement
211  *  @hw: pointer to the HW structure
212  *  @mbx_id: id of mailbox to write
213  *
214  *  returns SUCCESS if it successfully received a message acknowledgement
215  **/
216 static s32 e1000_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
217 {
218 	struct e1000_mbx_info *mbx = &hw->mbx;
219 	int countdown = mbx->timeout;
220 
221 	DEBUGFUNC("e1000_poll_for_ack");
222 
223 	if (!countdown || !mbx->ops.check_for_ack)
224 		goto out;
225 
226 	while (countdown && mbx->ops.check_for_ack(hw, mbx_id)) {
227 		countdown--;
228 		if (!countdown)
229 			break;
230 		usec_delay(mbx->usec_delay);
231 	}
232 
233 	/* if we failed, all future posted messages fail until reset */
234 	if (!countdown)
235 		mbx->timeout = 0;
236 out:
237 	return countdown ? E1000_SUCCESS : -E1000_ERR_MBX;
238 }
239 
240 /**
241  *  e1000_read_posted_mbx - Wait for message notification and receive message
242  *  @hw: pointer to the HW structure
243  *  @msg: The message buffer
244  *  @size: Length of buffer
245  *  @mbx_id: id of mailbox to write
246  *
247  *  returns SUCCESS if it successfully received a message notification and
248  *  copied it into the receive buffer.
249  **/
250 s32 e1000_read_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
251 {
252 	struct e1000_mbx_info *mbx = &hw->mbx;
253 	s32 ret_val = -E1000_ERR_MBX;
254 
255 	DEBUGFUNC("e1000_read_posted_mbx");
256 
257 	if (!mbx->ops.read)
258 		goto out;
259 
260 	ret_val = e1000_poll_for_msg(hw, mbx_id);
261 
262 	/* if ack received read message, otherwise we timed out */
263 	if (!ret_val)
264 		ret_val = mbx->ops.read(hw, msg, size, mbx_id);
265 out:
266 	return ret_val;
267 }
268 
269 /**
270  *  e1000_write_posted_mbx - Write a message to the mailbox, wait for ack
271  *  @hw: pointer to the HW structure
272  *  @msg: The message buffer
273  *  @size: Length of buffer
274  *  @mbx_id: id of mailbox to write
275  *
276  *  returns SUCCESS if it successfully copied message into the buffer and
277  *  received an ack to that message within delay * timeout period
278  **/
279 s32 e1000_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
280 {
281 	struct e1000_mbx_info *mbx = &hw->mbx;
282 	s32 ret_val = -E1000_ERR_MBX;
283 
284 	DEBUGFUNC("e1000_write_posted_mbx");
285 
286 	/* exit if either we can't write or there isn't a defined timeout */
287 	if (!mbx->ops.write || !mbx->timeout)
288 		goto out;
289 
290 	/* send msg */
291 	ret_val = mbx->ops.write(hw, msg, size, mbx_id);
292 
293 	/* if msg sent wait until we receive an ack */
294 	if (!ret_val)
295 		ret_val = e1000_poll_for_ack(hw, mbx_id);
296 out:
297 	return ret_val;
298 }
299 
300 /**
301  *  e1000_init_mbx_ops_generic - Initialize mbx function pointers
302  *  @hw: pointer to the HW structure
303  *
304  *  Sets the function pointers to no-op functions
305  **/
306 void e1000_init_mbx_ops_generic(struct e1000_hw *hw)
307 {
308 	struct e1000_mbx_info *mbx = &hw->mbx;
309 	mbx->ops.init_params = e1000_null_ops_generic;
310 	mbx->ops.read = e1000_null_mbx_transact;
311 	mbx->ops.write = e1000_null_mbx_transact;
312 	mbx->ops.check_for_msg = e1000_null_mbx_check_for_flag;
313 	mbx->ops.check_for_ack = e1000_null_mbx_check_for_flag;
314 	mbx->ops.check_for_rst = e1000_null_mbx_check_for_flag;
315 	mbx->ops.read_posted = e1000_read_posted_mbx;
316 	mbx->ops.write_posted = e1000_write_posted_mbx;
317 }
318 
319 /**
320  *  e1000_read_v2p_mailbox - read v2p mailbox
321  *  @hw: pointer to the HW structure
322  *
323  *  This function is used to read the v2p mailbox without losing the read to
324  *  clear status bits.
325  **/
326 static u32 e1000_read_v2p_mailbox(struct e1000_hw *hw)
327 {
328 	u32 v2p_mailbox = E1000_READ_REG(hw, E1000_V2PMAILBOX(0));
329 
330 	v2p_mailbox |= hw->dev_spec.vf.v2p_mailbox;
331 	hw->dev_spec.vf.v2p_mailbox |= v2p_mailbox & E1000_V2PMAILBOX_R2C_BITS;
332 
333 	return v2p_mailbox;
334 }
335 
336 /**
337  *  e1000_check_for_bit_vf - Determine if a status bit was set
338  *  @hw: pointer to the HW structure
339  *  @mask: bitmask for bits to be tested and cleared
340  *
341  *  This function is used to check for the read to clear bits within
342  *  the V2P mailbox.
343  **/
344 static s32 e1000_check_for_bit_vf(struct e1000_hw *hw, u32 mask)
345 {
346 	u32 v2p_mailbox = e1000_read_v2p_mailbox(hw);
347 	s32 ret_val = -E1000_ERR_MBX;
348 
349 	if (v2p_mailbox & mask)
350 		ret_val = E1000_SUCCESS;
351 
352 	hw->dev_spec.vf.v2p_mailbox &= ~mask;
353 
354 	return ret_val;
355 }
356 
357 /**
358  *  e1000_check_for_msg_vf - checks to see if the PF has sent mail
359  *  @hw: pointer to the HW structure
360  *  @mbx_id: id of mailbox to check
361  *
362  *  returns SUCCESS if the PF has set the Status bit or else ERR_MBX
363  **/
364 static s32 e1000_check_for_msg_vf(struct e1000_hw *hw,
365 				  u16 E1000_UNUSEDARG mbx_id)
366 {
367 	s32 ret_val = -E1000_ERR_MBX;
368 
369 	DEBUGFUNC("e1000_check_for_msg_vf");
370 
371 	if (!e1000_check_for_bit_vf(hw, E1000_V2PMAILBOX_PFSTS)) {
372 		ret_val = E1000_SUCCESS;
373 		hw->mbx.stats.reqs++;
374 	}
375 
376 	return ret_val;
377 }
378 
379 /**
380  *  e1000_check_for_ack_vf - checks to see if the PF has ACK'd
381  *  @hw: pointer to the HW structure
382  *  @mbx_id: id of mailbox to check
383  *
384  *  returns SUCCESS if the PF has set the ACK bit or else ERR_MBX
385  **/
386 static s32 e1000_check_for_ack_vf(struct e1000_hw *hw,
387 				  u16 E1000_UNUSEDARG mbx_id)
388 {
389 	s32 ret_val = -E1000_ERR_MBX;
390 
391 	DEBUGFUNC("e1000_check_for_ack_vf");
392 
393 	if (!e1000_check_for_bit_vf(hw, E1000_V2PMAILBOX_PFACK)) {
394 		ret_val = E1000_SUCCESS;
395 		hw->mbx.stats.acks++;
396 	}
397 
398 	return ret_val;
399 }
400 
401 /**
402  *  e1000_check_for_rst_vf - checks to see if the PF has reset
403  *  @hw: pointer to the HW structure
404  *  @mbx_id: id of mailbox to check
405  *
406  *  returns true if the PF has set the reset done bit or else false
407  **/
408 static s32 e1000_check_for_rst_vf(struct e1000_hw *hw,
409 				  u16 E1000_UNUSEDARG mbx_id)
410 {
411 	s32 ret_val = -E1000_ERR_MBX;
412 
413 	DEBUGFUNC("e1000_check_for_rst_vf");
414 
415 	if (!e1000_check_for_bit_vf(hw, (E1000_V2PMAILBOX_RSTD |
416 					 E1000_V2PMAILBOX_RSTI))) {
417 		ret_val = E1000_SUCCESS;
418 		hw->mbx.stats.rsts++;
419 	}
420 
421 	return ret_val;
422 }
423 
424 /**
425  *  e1000_obtain_mbx_lock_vf - obtain mailbox lock
426  *  @hw: pointer to the HW structure
427  *
428  *  return SUCCESS if we obtained the mailbox lock
429  **/
430 static s32 e1000_obtain_mbx_lock_vf(struct e1000_hw *hw)
431 {
432 	s32 ret_val = -E1000_ERR_MBX;
433 	int count = 10;
434 
435 	DEBUGFUNC("e1000_obtain_mbx_lock_vf");
436 
437 	do {
438 		/* Take ownership of the buffer */
439 		E1000_WRITE_REG(hw, E1000_V2PMAILBOX(0), E1000_V2PMAILBOX_VFU);
440 
441 		/* reserve mailbox for vf use */
442 		if (e1000_read_v2p_mailbox(hw) & E1000_V2PMAILBOX_VFU) {
443 			ret_val = E1000_SUCCESS;
444 			break;
445 		}
446 		usec_delay(1000);
447 	} while (count-- > 0);
448 
449 	return ret_val;
450 }
451 
452 /**
453  *  e1000_write_mbx_vf - Write a message to the mailbox
454  *  @hw: pointer to the HW structure
455  *  @msg: The message buffer
456  *  @size: Length of buffer
457  *  @mbx_id: id of mailbox to write
458  *
459  *  returns SUCCESS if it successfully copied message into the buffer
460  **/
461 static s32 e1000_write_mbx_vf(struct e1000_hw *hw, u32 *msg, u16 size,
462 			      u16 E1000_UNUSEDARG mbx_id)
463 {
464 	s32 ret_val;
465 	u16 i;
466 
467 
468 	DEBUGFUNC("e1000_write_mbx_vf");
469 
470 	/* lock the mailbox to prevent pf/vf race condition */
471 	ret_val = e1000_obtain_mbx_lock_vf(hw);
472 	if (ret_val)
473 		goto out_no_write;
474 
475 	/* flush msg and acks as we are overwriting the message buffer */
476 	e1000_check_for_msg_vf(hw, 0);
477 	e1000_check_for_ack_vf(hw, 0);
478 
479 	/* copy the caller specified message to the mailbox memory buffer */
480 	for (i = 0; i < size; i++)
481 		E1000_WRITE_REG_ARRAY(hw, E1000_VMBMEM(0), i, msg[i]);
482 
483 	/* update stats */
484 	hw->mbx.stats.msgs_tx++;
485 
486 	/* Drop VFU and interrupt the PF to tell it a message has been sent */
487 	E1000_WRITE_REG(hw, E1000_V2PMAILBOX(0), E1000_V2PMAILBOX_REQ);
488 
489 out_no_write:
490 	return ret_val;
491 }
492 
493 /**
494  *  e1000_read_mbx_vf - Reads a message from the inbox intended for vf
495  *  @hw: pointer to the HW structure
496  *  @msg: The message buffer
497  *  @size: Length of buffer
498  *  @mbx_id: id of mailbox to read
499  *
500  *  returns SUCCESS if it successfully read message from buffer
501  **/
502 static s32 e1000_read_mbx_vf(struct e1000_hw *hw, u32 *msg, u16 size,
503 			     u16 E1000_UNUSEDARG mbx_id)
504 {
505 	s32 ret_val = E1000_SUCCESS;
506 	u16 i;
507 
508 	DEBUGFUNC("e1000_read_mbx_vf");
509 
510 	/* lock the mailbox to prevent pf/vf race condition */
511 	ret_val = e1000_obtain_mbx_lock_vf(hw);
512 	if (ret_val)
513 		goto out_no_read;
514 
515 	/* copy the message from the mailbox memory buffer */
516 	for (i = 0; i < size; i++)
517 		msg[i] = E1000_READ_REG_ARRAY(hw, E1000_VMBMEM(0), i);
518 
519 	/* Acknowledge receipt and release mailbox, then we're done */
520 	E1000_WRITE_REG(hw, E1000_V2PMAILBOX(0), E1000_V2PMAILBOX_ACK);
521 
522 	/* update stats */
523 	hw->mbx.stats.msgs_rx++;
524 
525 out_no_read:
526 	return ret_val;
527 }
528 
529 /**
530  *  e1000_init_mbx_params_vf - set initial values for vf mailbox
531  *  @hw: pointer to the HW structure
532  *
533  *  Initializes the hw->mbx struct to correct values for vf mailbox
534  */
535 s32 e1000_init_mbx_params_vf(struct e1000_hw *hw)
536 {
537 	struct e1000_mbx_info *mbx = &hw->mbx;
538 
539 	/* start mailbox as timed out and let the reset_hw call set the timeout
540 	 * value to begin communications */
541 	mbx->timeout = 0;
542 	mbx->usec_delay = E1000_VF_MBX_INIT_DELAY;
543 
544 	mbx->size = E1000_VFMAILBOX_SIZE;
545 
546 	mbx->ops.read = e1000_read_mbx_vf;
547 	mbx->ops.write = e1000_write_mbx_vf;
548 	mbx->ops.read_posted = e1000_read_posted_mbx;
549 	mbx->ops.write_posted = e1000_write_posted_mbx;
550 	mbx->ops.check_for_msg = e1000_check_for_msg_vf;
551 	mbx->ops.check_for_ack = e1000_check_for_ack_vf;
552 	mbx->ops.check_for_rst = e1000_check_for_rst_vf;
553 
554 	mbx->stats.msgs_tx = 0;
555 	mbx->stats.msgs_rx = 0;
556 	mbx->stats.reqs = 0;
557 	mbx->stats.acks = 0;
558 	mbx->stats.rsts = 0;
559 
560 	return E1000_SUCCESS;
561 }
562 
563 static s32 e1000_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
564 {
565 	u32 mbvficr = E1000_READ_REG(hw, E1000_MBVFICR);
566 	s32 ret_val = -E1000_ERR_MBX;
567 
568 	if (mbvficr & mask) {
569 		ret_val = E1000_SUCCESS;
570 		E1000_WRITE_REG(hw, E1000_MBVFICR, mask);
571 	}
572 
573 	return ret_val;
574 }
575 
576 /**
577  *  e1000_check_for_msg_pf - checks to see if the VF has sent mail
578  *  @hw: pointer to the HW structure
579  *  @vf_number: the VF index
580  *
581  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
582  **/
583 static s32 e1000_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
584 {
585 	s32 ret_val = -E1000_ERR_MBX;
586 
587 	DEBUGFUNC("e1000_check_for_msg_pf");
588 
589 	if (!e1000_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
590 		ret_val = E1000_SUCCESS;
591 		hw->mbx.stats.reqs++;
592 	}
593 
594 	return ret_val;
595 }
596 
597 /**
598  *  e1000_check_for_ack_pf - checks to see if the VF has ACKed
599  *  @hw: pointer to the HW structure
600  *  @vf_number: the VF index
601  *
602  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
603  **/
604 static s32 e1000_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
605 {
606 	s32 ret_val = -E1000_ERR_MBX;
607 
608 	DEBUGFUNC("e1000_check_for_ack_pf");
609 
610 	if (!e1000_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
611 		ret_val = E1000_SUCCESS;
612 		hw->mbx.stats.acks++;
613 	}
614 
615 	return ret_val;
616 }
617 
618 /**
619  *  e1000_check_for_rst_pf - checks to see if the VF has reset
620  *  @hw: pointer to the HW structure
621  *  @vf_number: the VF index
622  *
623  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
624  **/
625 static s32 e1000_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
626 {
627 	u32 vflre = E1000_READ_REG(hw, E1000_VFLRE);
628 	s32 ret_val = -E1000_ERR_MBX;
629 
630 	DEBUGFUNC("e1000_check_for_rst_pf");
631 
632 	if (vflre & (1 << vf_number)) {
633 		ret_val = E1000_SUCCESS;
634 		E1000_WRITE_REG(hw, E1000_VFLRE, (1 << vf_number));
635 		hw->mbx.stats.rsts++;
636 	}
637 
638 	return ret_val;
639 }
640 
641 /**
642  *  e1000_obtain_mbx_lock_pf - obtain mailbox lock
643  *  @hw: pointer to the HW structure
644  *  @vf_number: the VF index
645  *
646  *  return SUCCESS if we obtained the mailbox lock
647  **/
648 static s32 e1000_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
649 {
650 	s32 ret_val = -E1000_ERR_MBX;
651 	u32 p2v_mailbox;
652 	int count = 10;
653 
654 	DEBUGFUNC("e1000_obtain_mbx_lock_pf");
655 
656 	do {
657 		/* Take ownership of the buffer */
658 		E1000_WRITE_REG(hw, E1000_P2VMAILBOX(vf_number),
659 				E1000_P2VMAILBOX_PFU);
660 
661 		/* reserve mailbox for pf use */
662 		p2v_mailbox = E1000_READ_REG(hw, E1000_P2VMAILBOX(vf_number));
663 		if (p2v_mailbox & E1000_P2VMAILBOX_PFU) {
664 			ret_val = E1000_SUCCESS;
665 			break;
666 		}
667 		usec_delay(1000);
668 	} while (count-- > 0);
669 
670 	return ret_val;
671 
672 }
673 
674 /**
675  *  e1000_write_mbx_pf - Places a message in the mailbox
676  *  @hw: pointer to the HW structure
677  *  @msg: The message buffer
678  *  @size: Length of buffer
679  *  @vf_number: the VF index
680  *
681  *  returns SUCCESS if it successfully copied message into the buffer
682  **/
683 static s32 e1000_write_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
684 			      u16 vf_number)
685 {
686 	s32 ret_val;
687 	u16 i;
688 
689 	DEBUGFUNC("e1000_write_mbx_pf");
690 
691 	/* lock the mailbox to prevent pf/vf race condition */
692 	ret_val = e1000_obtain_mbx_lock_pf(hw, vf_number);
693 	if (ret_val)
694 		goto out_no_write;
695 
696 	/* flush msg and acks as we are overwriting the message buffer */
697 	e1000_check_for_msg_pf(hw, vf_number);
698 	e1000_check_for_ack_pf(hw, vf_number);
699 
700 	/* copy the caller specified message to the mailbox memory buffer */
701 	for (i = 0; i < size; i++)
702 		E1000_WRITE_REG_ARRAY(hw, E1000_VMBMEM(vf_number), i, msg[i]);
703 
704 	/* Interrupt VF to tell it a message has been sent and release buffer*/
705 	E1000_WRITE_REG(hw, E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_STS);
706 
707 	/* update stats */
708 	hw->mbx.stats.msgs_tx++;
709 
710 out_no_write:
711 	return ret_val;
712 
713 }
714 
715 /**
716  *  e1000_read_mbx_pf - Read a message from the mailbox
717  *  @hw: pointer to the HW structure
718  *  @msg: The message buffer
719  *  @size: Length of buffer
720  *  @vf_number: the VF index
721  *
722  *  This function copies a message from the mailbox buffer to the caller's
723  *  memory buffer.  The presumption is that the caller knows that there was
724  *  a message due to a VF request so no polling for message is needed.
725  **/
726 static s32 e1000_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
727 			     u16 vf_number)
728 {
729 	s32 ret_val;
730 	u16 i;
731 
732 	DEBUGFUNC("e1000_read_mbx_pf");
733 
734 	/* lock the mailbox to prevent pf/vf race condition */
735 	ret_val = e1000_obtain_mbx_lock_pf(hw, vf_number);
736 	if (ret_val)
737 		goto out_no_read;
738 
739 	/* copy the message to the mailbox memory buffer */
740 	for (i = 0; i < size; i++)
741 		msg[i] = E1000_READ_REG_ARRAY(hw, E1000_VMBMEM(vf_number), i);
742 
743 	/* Acknowledge the message and release buffer */
744 	E1000_WRITE_REG(hw, E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_ACK);
745 
746 	/* update stats */
747 	hw->mbx.stats.msgs_rx++;
748 
749 out_no_read:
750 	return ret_val;
751 }
752 
753 /**
754  *  e1000_init_mbx_params_pf - set initial values for pf mailbox
755  *  @hw: pointer to the HW structure
756  *
757  *  Initializes the hw->mbx struct to correct values for pf mailbox
758  */
759 s32 e1000_init_mbx_params_pf(struct e1000_hw *hw)
760 {
761 	struct e1000_mbx_info *mbx = &hw->mbx;
762 
763 	switch (hw->mac.type) {
764 	case e1000_82576:
765 	case e1000_i350:
766 	case e1000_i354:
767 		mbx->timeout = 0;
768 		mbx->usec_delay = 0;
769 
770 		mbx->size = E1000_VFMAILBOX_SIZE;
771 
772 		mbx->ops.read = e1000_read_mbx_pf;
773 		mbx->ops.write = e1000_write_mbx_pf;
774 		mbx->ops.read_posted = e1000_read_posted_mbx;
775 		mbx->ops.write_posted = e1000_write_posted_mbx;
776 		mbx->ops.check_for_msg = e1000_check_for_msg_pf;
777 		mbx->ops.check_for_ack = e1000_check_for_ack_pf;
778 		mbx->ops.check_for_rst = e1000_check_for_rst_pf;
779 
780 		mbx->stats.msgs_tx = 0;
781 		mbx->stats.msgs_rx = 0;
782 		mbx->stats.reqs = 0;
783 		mbx->stats.acks = 0;
784 		mbx->stats.rsts = 0;
785 		/* FALLTHROUGH */
786 	default:
787 		return E1000_SUCCESS;
788 	}
789 }
790 
791