1 /*******************************************************************************
2 
3   Intel(R) Gigabit Ethernet Linux driver
4   Copyright(c) 2007-2014 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   You should have received a copy of the GNU General Public License along with
16   this program; if not, see <http://www.gnu.org/licenses/>.
17 
18   The full GNU General Public License is included in this distribution in
19   the file called "COPYING".
20 
21   Contact Information:
22   e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
23   Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
24 
25 *******************************************************************************/
26 
27 #include "e1000_mbx.h"
28 
29 /**
30  *  igb_read_mbx - Reads a message from the mailbox
31  *  @hw: pointer to the HW structure
32  *  @msg: The message buffer
33  *  @size: Length of buffer
34  *  @mbx_id: id of mailbox to read
35  *
36  *  returns SUCCESS if it successfully read message from buffer
37  **/
38 s32 igb_read_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
39 {
40 	struct e1000_mbx_info *mbx = &hw->mbx;
41 	s32 ret_val = -E1000_ERR_MBX;
42 
43 	/* limit read to size of mailbox */
44 	if (size > mbx->size)
45 		size = mbx->size;
46 
47 	if (mbx->ops.read)
48 		ret_val = mbx->ops.read(hw, msg, size, mbx_id);
49 
50 	return ret_val;
51 }
52 
53 /**
54  *  igb_write_mbx - Write a message to the mailbox
55  *  @hw: pointer to the HW structure
56  *  @msg: The message buffer
57  *  @size: Length of buffer
58  *  @mbx_id: id of mailbox to write
59  *
60  *  returns SUCCESS if it successfully copied message into the buffer
61  **/
62 s32 igb_write_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
63 {
64 	struct e1000_mbx_info *mbx = &hw->mbx;
65 	s32 ret_val = 0;
66 
67 	if (size > mbx->size)
68 		ret_val = -E1000_ERR_MBX;
69 
70 	else if (mbx->ops.write)
71 		ret_val = mbx->ops.write(hw, msg, size, mbx_id);
72 
73 	return ret_val;
74 }
75 
76 /**
77  *  igb_check_for_msg - checks to see if someone sent us mail
78  *  @hw: pointer to the HW structure
79  *  @mbx_id: id of mailbox to check
80  *
81  *  returns SUCCESS if the Status bit was found or else ERR_MBX
82  **/
83 s32 igb_check_for_msg(struct e1000_hw *hw, u16 mbx_id)
84 {
85 	struct e1000_mbx_info *mbx = &hw->mbx;
86 	s32 ret_val = -E1000_ERR_MBX;
87 
88 	if (mbx->ops.check_for_msg)
89 		ret_val = mbx->ops.check_for_msg(hw, mbx_id);
90 
91 	return ret_val;
92 }
93 
94 /**
95  *  igb_check_for_ack - checks to see if someone sent us ACK
96  *  @hw: pointer to the HW structure
97  *  @mbx_id: id of mailbox to check
98  *
99  *  returns SUCCESS if the Status bit was found or else ERR_MBX
100  **/
101 s32 igb_check_for_ack(struct e1000_hw *hw, u16 mbx_id)
102 {
103 	struct e1000_mbx_info *mbx = &hw->mbx;
104 	s32 ret_val = -E1000_ERR_MBX;
105 
106 	if (mbx->ops.check_for_ack)
107 		ret_val = mbx->ops.check_for_ack(hw, mbx_id);
108 
109 	return ret_val;
110 }
111 
112 /**
113  *  igb_check_for_rst - checks to see if other side has reset
114  *  @hw: pointer to the HW structure
115  *  @mbx_id: id of mailbox to check
116  *
117  *  returns SUCCESS if the Status bit was found or else ERR_MBX
118  **/
119 s32 igb_check_for_rst(struct e1000_hw *hw, u16 mbx_id)
120 {
121 	struct e1000_mbx_info *mbx = &hw->mbx;
122 	s32 ret_val = -E1000_ERR_MBX;
123 
124 	if (mbx->ops.check_for_rst)
125 		ret_val = mbx->ops.check_for_rst(hw, mbx_id);
126 
127 	return ret_val;
128 }
129 
130 /**
131  *  igb_poll_for_msg - Wait for message notification
132  *  @hw: pointer to the HW structure
133  *  @mbx_id: id of mailbox to write
134  *
135  *  returns SUCCESS if it successfully received a message notification
136  **/
137 static s32 igb_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
138 {
139 	struct e1000_mbx_info *mbx = &hw->mbx;
140 	int countdown = mbx->timeout;
141 
142 	if (!countdown || !mbx->ops.check_for_msg)
143 		goto out;
144 
145 	while (countdown && mbx->ops.check_for_msg(hw, mbx_id)) {
146 		countdown--;
147 		if (!countdown)
148 			break;
149 		udelay(mbx->usec_delay);
150 	}
151 
152 	/* if we failed, all future posted messages fail until reset */
153 	if (!countdown)
154 		mbx->timeout = 0;
155 out:
156 	return countdown ? 0 : -E1000_ERR_MBX;
157 }
158 
159 /**
160  *  igb_poll_for_ack - Wait for message acknowledgement
161  *  @hw: pointer to the HW structure
162  *  @mbx_id: id of mailbox to write
163  *
164  *  returns SUCCESS if it successfully received a message acknowledgement
165  **/
166 static s32 igb_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
167 {
168 	struct e1000_mbx_info *mbx = &hw->mbx;
169 	int countdown = mbx->timeout;
170 
171 	if (!countdown || !mbx->ops.check_for_ack)
172 		goto out;
173 
174 	while (countdown && mbx->ops.check_for_ack(hw, mbx_id)) {
175 		countdown--;
176 		if (!countdown)
177 			break;
178 		udelay(mbx->usec_delay);
179 	}
180 
181 	/* if we failed, all future posted messages fail until reset */
182 	if (!countdown)
183 		mbx->timeout = 0;
184 out:
185 	return countdown ? 0 : -E1000_ERR_MBX;
186 }
187 
188 /**
189  *  igb_read_posted_mbx - Wait for message notification and receive message
190  *  @hw: pointer to the HW structure
191  *  @msg: The message buffer
192  *  @size: Length of buffer
193  *  @mbx_id: id of mailbox to write
194  *
195  *  returns SUCCESS if it successfully received a message notification and
196  *  copied it into the receive buffer.
197  **/
198 static s32 igb_read_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size,
199 			       u16 mbx_id)
200 {
201 	struct e1000_mbx_info *mbx = &hw->mbx;
202 	s32 ret_val = -E1000_ERR_MBX;
203 
204 	if (!mbx->ops.read)
205 		goto out;
206 
207 	ret_val = igb_poll_for_msg(hw, mbx_id);
208 
209 	if (!ret_val)
210 		ret_val = mbx->ops.read(hw, msg, size, mbx_id);
211 out:
212 	return ret_val;
213 }
214 
215 /**
216  *  igb_write_posted_mbx - Write a message to the mailbox, wait for ack
217  *  @hw: pointer to the HW structure
218  *  @msg: The message buffer
219  *  @size: Length of buffer
220  *  @mbx_id: id of mailbox to write
221  *
222  *  returns SUCCESS if it successfully copied message into the buffer and
223  *  received an ack to that message within delay * timeout period
224  **/
225 static s32 igb_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size,
226 				u16 mbx_id)
227 {
228 	struct e1000_mbx_info *mbx = &hw->mbx;
229 	s32 ret_val = -E1000_ERR_MBX;
230 
231 	/* exit if either we can't write or there isn't a defined timeout */
232 	if (!mbx->ops.write || !mbx->timeout)
233 		goto out;
234 
235 	/* send msg */
236 	ret_val = mbx->ops.write(hw, msg, size, mbx_id);
237 
238 	/* if msg sent wait until we receive an ack */
239 	if (!ret_val)
240 		ret_val = igb_poll_for_ack(hw, mbx_id);
241 out:
242 	return ret_val;
243 }
244 
245 static s32 igb_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
246 {
247 	u32 mbvficr = rd32(E1000_MBVFICR);
248 	s32 ret_val = -E1000_ERR_MBX;
249 
250 	if (mbvficr & mask) {
251 		ret_val = 0;
252 		wr32(E1000_MBVFICR, mask);
253 	}
254 
255 	return ret_val;
256 }
257 
258 /**
259  *  igb_check_for_msg_pf - checks to see if the VF has sent mail
260  *  @hw: pointer to the HW structure
261  *  @vf_number: the VF index
262  *
263  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
264  **/
265 static s32 igb_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
266 {
267 	s32 ret_val = -E1000_ERR_MBX;
268 
269 	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
270 		ret_val = 0;
271 		hw->mbx.stats.reqs++;
272 	}
273 
274 	return ret_val;
275 }
276 
277 /**
278  *  igb_check_for_ack_pf - checks to see if the VF has ACKed
279  *  @hw: pointer to the HW structure
280  *  @vf_number: the VF index
281  *
282  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
283  **/
284 static s32 igb_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
285 {
286 	s32 ret_val = -E1000_ERR_MBX;
287 
288 	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
289 		ret_val = 0;
290 		hw->mbx.stats.acks++;
291 	}
292 
293 	return ret_val;
294 }
295 
296 /**
297  *  igb_check_for_rst_pf - checks to see if the VF has reset
298  *  @hw: pointer to the HW structure
299  *  @vf_number: the VF index
300  *
301  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
302  **/
303 static s32 igb_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
304 {
305 	u32 vflre = rd32(E1000_VFLRE);
306 	s32 ret_val = -E1000_ERR_MBX;
307 
308 	if (vflre & (1 << vf_number)) {
309 		ret_val = 0;
310 		wr32(E1000_VFLRE, (1 << vf_number));
311 		hw->mbx.stats.rsts++;
312 	}
313 
314 	return ret_val;
315 }
316 
317 /**
318  *  igb_obtain_mbx_lock_pf - obtain mailbox lock
319  *  @hw: pointer to the HW structure
320  *  @vf_number: the VF index
321  *
322  *  return SUCCESS if we obtained the mailbox lock
323  **/
324 static s32 igb_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
325 {
326 	s32 ret_val = -E1000_ERR_MBX;
327 	u32 p2v_mailbox;
328 
329 	/* Take ownership of the buffer */
330 	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_PFU);
331 
332 	/* reserve mailbox for vf use */
333 	p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
334 	if (p2v_mailbox & E1000_P2VMAILBOX_PFU)
335 		ret_val = 0;
336 
337 	return ret_val;
338 }
339 
340 /**
341  *  igb_write_mbx_pf - Places a message in the mailbox
342  *  @hw: pointer to the HW structure
343  *  @msg: The message buffer
344  *  @size: Length of buffer
345  *  @vf_number: the VF index
346  *
347  *  returns SUCCESS if it successfully copied message into the buffer
348  **/
349 static s32 igb_write_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
350 			    u16 vf_number)
351 {
352 	s32 ret_val;
353 	u16 i;
354 
355 	/* lock the mailbox to prevent pf/vf race condition */
356 	ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
357 	if (ret_val)
358 		goto out_no_write;
359 
360 	/* flush msg and acks as we are overwriting the message buffer */
361 	igb_check_for_msg_pf(hw, vf_number);
362 	igb_check_for_ack_pf(hw, vf_number);
363 
364 	/* copy the caller specified message to the mailbox memory buffer */
365 	for (i = 0; i < size; i++)
366 		array_wr32(E1000_VMBMEM(vf_number), i, msg[i]);
367 
368 	/* Interrupt VF to tell it a message has been sent and release buffer*/
369 	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_STS);
370 
371 	/* update stats */
372 	hw->mbx.stats.msgs_tx++;
373 
374 out_no_write:
375 	return ret_val;
376 
377 }
378 
379 /**
380  *  igb_read_mbx_pf - Read a message from the mailbox
381  *  @hw: pointer to the HW structure
382  *  @msg: The message buffer
383  *  @size: Length of buffer
384  *  @vf_number: the VF index
385  *
386  *  This function copies a message from the mailbox buffer to the caller's
387  *  memory buffer.  The presumption is that the caller knows that there was
388  *  a message due to a VF request so no polling for message is needed.
389  **/
390 static s32 igb_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
391 			   u16 vf_number)
392 {
393 	s32 ret_val;
394 	u16 i;
395 
396 	/* lock the mailbox to prevent pf/vf race condition */
397 	ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
398 	if (ret_val)
399 		goto out_no_read;
400 
401 	/* copy the message to the mailbox memory buffer */
402 	for (i = 0; i < size; i++)
403 		msg[i] = array_rd32(E1000_VMBMEM(vf_number), i);
404 
405 	/* Acknowledge the message and release buffer */
406 	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_ACK);
407 
408 	/* update stats */
409 	hw->mbx.stats.msgs_rx++;
410 
411 out_no_read:
412 	return ret_val;
413 }
414 
415 /**
416  *  e1000_init_mbx_params_pf - set initial values for pf mailbox
417  *  @hw: pointer to the HW structure
418  *
419  *  Initializes the hw->mbx struct to correct values for pf mailbox
420  */
421 s32 igb_init_mbx_params_pf(struct e1000_hw *hw)
422 {
423 	struct e1000_mbx_info *mbx = &hw->mbx;
424 
425 	mbx->timeout = 0;
426 	mbx->usec_delay = 0;
427 
428 	mbx->size = E1000_VFMAILBOX_SIZE;
429 
430 	mbx->ops.read = igb_read_mbx_pf;
431 	mbx->ops.write = igb_write_mbx_pf;
432 	mbx->ops.read_posted = igb_read_posted_mbx;
433 	mbx->ops.write_posted = igb_write_posted_mbx;
434 	mbx->ops.check_for_msg = igb_check_for_msg_pf;
435 	mbx->ops.check_for_ack = igb_check_for_ack_pf;
436 	mbx->ops.check_for_rst = igb_check_for_rst_pf;
437 
438 	mbx->stats.msgs_tx = 0;
439 	mbx->stats.msgs_rx = 0;
440 	mbx->stats.reqs = 0;
441 	mbx->stats.acks = 0;
442 	mbx->stats.rsts = 0;
443 
444 	return 0;
445 }
446 
447