1 /* Intel(R) Gigabit Ethernet Linux driver
2  * Copyright(c) 2007-2014 Intel Corporation.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, see <http://www.gnu.org/licenses/>.
15  *
16  * The full GNU General Public License is included in this distribution in
17  * the file called "COPYING".
18  *
19  * Contact Information:
20  * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
21  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
22  */
23 
24 #include "e1000_mbx.h"
25 
26 /**
27  *  igb_read_mbx - Reads a message from the mailbox
28  *  @hw: pointer to the HW structure
29  *  @msg: The message buffer
30  *  @size: Length of buffer
31  *  @mbx_id: id of mailbox to read
32  *
33  *  returns SUCCESS if it successfully read message from buffer
34  **/
35 s32 igb_read_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
36 {
37 	struct e1000_mbx_info *mbx = &hw->mbx;
38 	s32 ret_val = -E1000_ERR_MBX;
39 
40 	/* limit read to size of mailbox */
41 	if (size > mbx->size)
42 		size = mbx->size;
43 
44 	if (mbx->ops.read)
45 		ret_val = mbx->ops.read(hw, msg, size, mbx_id);
46 
47 	return ret_val;
48 }
49 
50 /**
51  *  igb_write_mbx - Write a message to the mailbox
52  *  @hw: pointer to the HW structure
53  *  @msg: The message buffer
54  *  @size: Length of buffer
55  *  @mbx_id: id of mailbox to write
56  *
57  *  returns SUCCESS if it successfully copied message into the buffer
58  **/
59 s32 igb_write_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
60 {
61 	struct e1000_mbx_info *mbx = &hw->mbx;
62 	s32 ret_val = 0;
63 
64 	if (size > mbx->size)
65 		ret_val = -E1000_ERR_MBX;
66 
67 	else if (mbx->ops.write)
68 		ret_val = mbx->ops.write(hw, msg, size, mbx_id);
69 
70 	return ret_val;
71 }
72 
73 /**
74  *  igb_check_for_msg - checks to see if someone sent us mail
75  *  @hw: pointer to the HW structure
76  *  @mbx_id: id of mailbox to check
77  *
78  *  returns SUCCESS if the Status bit was found or else ERR_MBX
79  **/
80 s32 igb_check_for_msg(struct e1000_hw *hw, u16 mbx_id)
81 {
82 	struct e1000_mbx_info *mbx = &hw->mbx;
83 	s32 ret_val = -E1000_ERR_MBX;
84 
85 	if (mbx->ops.check_for_msg)
86 		ret_val = mbx->ops.check_for_msg(hw, mbx_id);
87 
88 	return ret_val;
89 }
90 
91 /**
92  *  igb_check_for_ack - checks to see if someone sent us ACK
93  *  @hw: pointer to the HW structure
94  *  @mbx_id: id of mailbox to check
95  *
96  *  returns SUCCESS if the Status bit was found or else ERR_MBX
97  **/
98 s32 igb_check_for_ack(struct e1000_hw *hw, u16 mbx_id)
99 {
100 	struct e1000_mbx_info *mbx = &hw->mbx;
101 	s32 ret_val = -E1000_ERR_MBX;
102 
103 	if (mbx->ops.check_for_ack)
104 		ret_val = mbx->ops.check_for_ack(hw, mbx_id);
105 
106 	return ret_val;
107 }
108 
109 /**
110  *  igb_check_for_rst - checks to see if other side has reset
111  *  @hw: pointer to the HW structure
112  *  @mbx_id: id of mailbox to check
113  *
114  *  returns SUCCESS if the Status bit was found or else ERR_MBX
115  **/
116 s32 igb_check_for_rst(struct e1000_hw *hw, u16 mbx_id)
117 {
118 	struct e1000_mbx_info *mbx = &hw->mbx;
119 	s32 ret_val = -E1000_ERR_MBX;
120 
121 	if (mbx->ops.check_for_rst)
122 		ret_val = mbx->ops.check_for_rst(hw, mbx_id);
123 
124 	return ret_val;
125 }
126 
127 /**
128  *  igb_poll_for_msg - Wait for message notification
129  *  @hw: pointer to the HW structure
130  *  @mbx_id: id of mailbox to write
131  *
132  *  returns SUCCESS if it successfully received a message notification
133  **/
134 static s32 igb_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
135 {
136 	struct e1000_mbx_info *mbx = &hw->mbx;
137 	int countdown = mbx->timeout;
138 
139 	if (!countdown || !mbx->ops.check_for_msg)
140 		goto out;
141 
142 	while (countdown && mbx->ops.check_for_msg(hw, mbx_id)) {
143 		countdown--;
144 		if (!countdown)
145 			break;
146 		udelay(mbx->usec_delay);
147 	}
148 
149 	/* if we failed, all future posted messages fail until reset */
150 	if (!countdown)
151 		mbx->timeout = 0;
152 out:
153 	return countdown ? 0 : -E1000_ERR_MBX;
154 }
155 
156 /**
157  *  igb_poll_for_ack - Wait for message acknowledgement
158  *  @hw: pointer to the HW structure
159  *  @mbx_id: id of mailbox to write
160  *
161  *  returns SUCCESS if it successfully received a message acknowledgement
162  **/
163 static s32 igb_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
164 {
165 	struct e1000_mbx_info *mbx = &hw->mbx;
166 	int countdown = mbx->timeout;
167 
168 	if (!countdown || !mbx->ops.check_for_ack)
169 		goto out;
170 
171 	while (countdown && mbx->ops.check_for_ack(hw, mbx_id)) {
172 		countdown--;
173 		if (!countdown)
174 			break;
175 		udelay(mbx->usec_delay);
176 	}
177 
178 	/* if we failed, all future posted messages fail until reset */
179 	if (!countdown)
180 		mbx->timeout = 0;
181 out:
182 	return countdown ? 0 : -E1000_ERR_MBX;
183 }
184 
185 /**
186  *  igb_read_posted_mbx - Wait for message notification and receive message
187  *  @hw: pointer to the HW structure
188  *  @msg: The message buffer
189  *  @size: Length of buffer
190  *  @mbx_id: id of mailbox to write
191  *
192  *  returns SUCCESS if it successfully received a message notification and
193  *  copied it into the receive buffer.
194  **/
195 static s32 igb_read_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size,
196 			       u16 mbx_id)
197 {
198 	struct e1000_mbx_info *mbx = &hw->mbx;
199 	s32 ret_val = -E1000_ERR_MBX;
200 
201 	if (!mbx->ops.read)
202 		goto out;
203 
204 	ret_val = igb_poll_for_msg(hw, mbx_id);
205 
206 	if (!ret_val)
207 		ret_val = mbx->ops.read(hw, msg, size, mbx_id);
208 out:
209 	return ret_val;
210 }
211 
212 /**
213  *  igb_write_posted_mbx - Write a message to the mailbox, wait for ack
214  *  @hw: pointer to the HW structure
215  *  @msg: The message buffer
216  *  @size: Length of buffer
217  *  @mbx_id: id of mailbox to write
218  *
219  *  returns SUCCESS if it successfully copied message into the buffer and
220  *  received an ack to that message within delay * timeout period
221  **/
222 static s32 igb_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size,
223 				u16 mbx_id)
224 {
225 	struct e1000_mbx_info *mbx = &hw->mbx;
226 	s32 ret_val = -E1000_ERR_MBX;
227 
228 	/* exit if either we can't write or there isn't a defined timeout */
229 	if (!mbx->ops.write || !mbx->timeout)
230 		goto out;
231 
232 	/* send msg */
233 	ret_val = mbx->ops.write(hw, msg, size, mbx_id);
234 
235 	/* if msg sent wait until we receive an ack */
236 	if (!ret_val)
237 		ret_val = igb_poll_for_ack(hw, mbx_id);
238 out:
239 	return ret_val;
240 }
241 
242 static s32 igb_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
243 {
244 	u32 mbvficr = rd32(E1000_MBVFICR);
245 	s32 ret_val = -E1000_ERR_MBX;
246 
247 	if (mbvficr & mask) {
248 		ret_val = 0;
249 		wr32(E1000_MBVFICR, mask);
250 	}
251 
252 	return ret_val;
253 }
254 
255 /**
256  *  igb_check_for_msg_pf - checks to see if the VF has sent mail
257  *  @hw: pointer to the HW structure
258  *  @vf_number: the VF index
259  *
260  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
261  **/
262 static s32 igb_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
263 {
264 	s32 ret_val = -E1000_ERR_MBX;
265 
266 	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
267 		ret_val = 0;
268 		hw->mbx.stats.reqs++;
269 	}
270 
271 	return ret_val;
272 }
273 
274 /**
275  *  igb_check_for_ack_pf - checks to see if the VF has ACKed
276  *  @hw: pointer to the HW structure
277  *  @vf_number: the VF index
278  *
279  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
280  **/
281 static s32 igb_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
282 {
283 	s32 ret_val = -E1000_ERR_MBX;
284 
285 	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
286 		ret_val = 0;
287 		hw->mbx.stats.acks++;
288 	}
289 
290 	return ret_val;
291 }
292 
293 /**
294  *  igb_check_for_rst_pf - checks to see if the VF has reset
295  *  @hw: pointer to the HW structure
296  *  @vf_number: the VF index
297  *
298  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
299  **/
300 static s32 igb_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
301 {
302 	u32 vflre = rd32(E1000_VFLRE);
303 	s32 ret_val = -E1000_ERR_MBX;
304 
305 	if (vflre & BIT(vf_number)) {
306 		ret_val = 0;
307 		wr32(E1000_VFLRE, BIT(vf_number));
308 		hw->mbx.stats.rsts++;
309 	}
310 
311 	return ret_val;
312 }
313 
314 /**
315  *  igb_obtain_mbx_lock_pf - obtain mailbox lock
316  *  @hw: pointer to the HW structure
317  *  @vf_number: the VF index
318  *
319  *  return SUCCESS if we obtained the mailbox lock
320  **/
321 static s32 igb_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
322 {
323 	s32 ret_val = -E1000_ERR_MBX;
324 	u32 p2v_mailbox;
325 	int count = 10;
326 
327 	do {
328 		/* Take ownership of the buffer */
329 		wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_PFU);
330 
331 		/* reserve mailbox for vf use */
332 		p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
333 		if (p2v_mailbox & E1000_P2VMAILBOX_PFU) {
334 			ret_val = 0;
335 			break;
336 		}
337 		udelay(1000);
338 	} while (count-- > 0);
339 
340 	return ret_val;
341 }
342 
343 /**
344  *  igb_write_mbx_pf - Places a message in the mailbox
345  *  @hw: pointer to the HW structure
346  *  @msg: The message buffer
347  *  @size: Length of buffer
348  *  @vf_number: the VF index
349  *
350  *  returns SUCCESS if it successfully copied message into the buffer
351  **/
352 static s32 igb_write_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
353 			    u16 vf_number)
354 {
355 	s32 ret_val;
356 	u16 i;
357 
358 	/* lock the mailbox to prevent pf/vf race condition */
359 	ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
360 	if (ret_val)
361 		goto out_no_write;
362 
363 	/* flush msg and acks as we are overwriting the message buffer */
364 	igb_check_for_msg_pf(hw, vf_number);
365 	igb_check_for_ack_pf(hw, vf_number);
366 
367 	/* copy the caller specified message to the mailbox memory buffer */
368 	for (i = 0; i < size; i++)
369 		array_wr32(E1000_VMBMEM(vf_number), i, msg[i]);
370 
371 	/* Interrupt VF to tell it a message has been sent and release buffer*/
372 	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_STS);
373 
374 	/* update stats */
375 	hw->mbx.stats.msgs_tx++;
376 
377 out_no_write:
378 	return ret_val;
379 
380 }
381 
382 /**
383  *  igb_read_mbx_pf - Read a message from the mailbox
384  *  @hw: pointer to the HW structure
385  *  @msg: The message buffer
386  *  @size: Length of buffer
387  *  @vf_number: the VF index
388  *
389  *  This function copies a message from the mailbox buffer to the caller's
390  *  memory buffer.  The presumption is that the caller knows that there was
391  *  a message due to a VF request so no polling for message is needed.
392  **/
393 static s32 igb_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
394 			   u16 vf_number)
395 {
396 	s32 ret_val;
397 	u16 i;
398 
399 	/* lock the mailbox to prevent pf/vf race condition */
400 	ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
401 	if (ret_val)
402 		goto out_no_read;
403 
404 	/* copy the message to the mailbox memory buffer */
405 	for (i = 0; i < size; i++)
406 		msg[i] = array_rd32(E1000_VMBMEM(vf_number), i);
407 
408 	/* Acknowledge the message and release buffer */
409 	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_ACK);
410 
411 	/* update stats */
412 	hw->mbx.stats.msgs_rx++;
413 
414 out_no_read:
415 	return ret_val;
416 }
417 
418 /**
419  *  e1000_init_mbx_params_pf - set initial values for pf mailbox
420  *  @hw: pointer to the HW structure
421  *
422  *  Initializes the hw->mbx struct to correct values for pf mailbox
423  */
424 s32 igb_init_mbx_params_pf(struct e1000_hw *hw)
425 {
426 	struct e1000_mbx_info *mbx = &hw->mbx;
427 
428 	mbx->timeout = 0;
429 	mbx->usec_delay = 0;
430 
431 	mbx->size = E1000_VFMAILBOX_SIZE;
432 
433 	mbx->ops.read = igb_read_mbx_pf;
434 	mbx->ops.write = igb_write_mbx_pf;
435 	mbx->ops.read_posted = igb_read_posted_mbx;
436 	mbx->ops.write_posted = igb_write_posted_mbx;
437 	mbx->ops.check_for_msg = igb_check_for_msg_pf;
438 	mbx->ops.check_for_ack = igb_check_for_ack_pf;
439 	mbx->ops.check_for_rst = igb_check_for_rst_pf;
440 
441 	mbx->stats.msgs_tx = 0;
442 	mbx->stats.msgs_rx = 0;
443 	mbx->stats.reqs = 0;
444 	mbx->stats.acks = 0;
445 	mbx->stats.rsts = 0;
446 
447 	return 0;
448 }
449 
450