1 /*******************************************************************************
2 
3   Intel(R) Gigabit Ethernet Linux driver
4   Copyright(c) 2007-2011 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, write to the Free Software Foundation, Inc.,
17   51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18 
19   The full GNU General Public License is included in this distribution in
20   the file called "COPYING".
21 
22   Contact Information:
23   e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
24   Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
25 
26 *******************************************************************************/
27 
28 #include "e1000_mbx.h"
29 
30 /**
31  *  igb_read_mbx - Reads a message from the mailbox
32  *  @hw: pointer to the HW structure
33  *  @msg: The message buffer
34  *  @size: Length of buffer
35  *  @mbx_id: id of mailbox to read
36  *
37  *  returns SUCCESS if it successfuly read message from buffer
38  **/
39 s32 igb_read_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
40 {
41 	struct e1000_mbx_info *mbx = &hw->mbx;
42 	s32 ret_val = -E1000_ERR_MBX;
43 
44 	/* limit read to size of mailbox */
45 	if (size > mbx->size)
46 		size = mbx->size;
47 
48 	if (mbx->ops.read)
49 		ret_val = mbx->ops.read(hw, msg, size, mbx_id);
50 
51 	return ret_val;
52 }
53 
54 /**
55  *  igb_write_mbx - Write a message to the mailbox
56  *  @hw: pointer to the HW structure
57  *  @msg: The message buffer
58  *  @size: Length of buffer
59  *  @mbx_id: id of mailbox to write
60  *
61  *  returns SUCCESS if it successfully copied message into the buffer
62  **/
63 s32 igb_write_mbx(struct e1000_hw *hw, u32 *msg, u16 size, u16 mbx_id)
64 {
65 	struct e1000_mbx_info *mbx = &hw->mbx;
66 	s32 ret_val = 0;
67 
68 	if (size > mbx->size)
69 		ret_val = -E1000_ERR_MBX;
70 
71 	else if (mbx->ops.write)
72 		ret_val = mbx->ops.write(hw, msg, size, mbx_id);
73 
74 	return ret_val;
75 }
76 
77 /**
78  *  igb_check_for_msg - checks to see if someone sent us mail
79  *  @hw: pointer to the HW structure
80  *  @mbx_id: id of mailbox to check
81  *
82  *  returns SUCCESS if the Status bit was found or else ERR_MBX
83  **/
84 s32 igb_check_for_msg(struct e1000_hw *hw, u16 mbx_id)
85 {
86 	struct e1000_mbx_info *mbx = &hw->mbx;
87 	s32 ret_val = -E1000_ERR_MBX;
88 
89 	if (mbx->ops.check_for_msg)
90 		ret_val = mbx->ops.check_for_msg(hw, mbx_id);
91 
92 	return ret_val;
93 }
94 
95 /**
96  *  igb_check_for_ack - checks to see if someone sent us ACK
97  *  @hw: pointer to the HW structure
98  *  @mbx_id: id of mailbox to check
99  *
100  *  returns SUCCESS if the Status bit was found or else ERR_MBX
101  **/
102 s32 igb_check_for_ack(struct e1000_hw *hw, u16 mbx_id)
103 {
104 	struct e1000_mbx_info *mbx = &hw->mbx;
105 	s32 ret_val = -E1000_ERR_MBX;
106 
107 	if (mbx->ops.check_for_ack)
108 		ret_val = mbx->ops.check_for_ack(hw, mbx_id);
109 
110 	return ret_val;
111 }
112 
113 /**
114  *  igb_check_for_rst - checks to see if other side has reset
115  *  @hw: pointer to the HW structure
116  *  @mbx_id: id of mailbox to check
117  *
118  *  returns SUCCESS if the Status bit was found or else ERR_MBX
119  **/
120 s32 igb_check_for_rst(struct e1000_hw *hw, u16 mbx_id)
121 {
122 	struct e1000_mbx_info *mbx = &hw->mbx;
123 	s32 ret_val = -E1000_ERR_MBX;
124 
125 	if (mbx->ops.check_for_rst)
126 		ret_val = mbx->ops.check_for_rst(hw, mbx_id);
127 
128 	return ret_val;
129 }
130 
131 /**
132  *  igb_poll_for_msg - Wait for message notification
133  *  @hw: pointer to the HW structure
134  *  @mbx_id: id of mailbox to write
135  *
136  *  returns SUCCESS if it successfully received a message notification
137  **/
138 static s32 igb_poll_for_msg(struct e1000_hw *hw, u16 mbx_id)
139 {
140 	struct e1000_mbx_info *mbx = &hw->mbx;
141 	int countdown = mbx->timeout;
142 
143 	if (!countdown || !mbx->ops.check_for_msg)
144 		goto out;
145 
146 	while (countdown && mbx->ops.check_for_msg(hw, mbx_id)) {
147 		countdown--;
148 		if (!countdown)
149 			break;
150 		udelay(mbx->usec_delay);
151 	}
152 
153 	/* if we failed, all future posted messages fail until reset */
154 	if (!countdown)
155 		mbx->timeout = 0;
156 out:
157 	return countdown ? 0 : -E1000_ERR_MBX;
158 }
159 
160 /**
161  *  igb_poll_for_ack - Wait for message acknowledgement
162  *  @hw: pointer to the HW structure
163  *  @mbx_id: id of mailbox to write
164  *
165  *  returns SUCCESS if it successfully received a message acknowledgement
166  **/
167 static s32 igb_poll_for_ack(struct e1000_hw *hw, u16 mbx_id)
168 {
169 	struct e1000_mbx_info *mbx = &hw->mbx;
170 	int countdown = mbx->timeout;
171 
172 	if (!countdown || !mbx->ops.check_for_ack)
173 		goto out;
174 
175 	while (countdown && mbx->ops.check_for_ack(hw, mbx_id)) {
176 		countdown--;
177 		if (!countdown)
178 			break;
179 		udelay(mbx->usec_delay);
180 	}
181 
182 	/* if we failed, all future posted messages fail until reset */
183 	if (!countdown)
184 		mbx->timeout = 0;
185 out:
186 	return countdown ? 0 : -E1000_ERR_MBX;
187 }
188 
189 /**
190  *  igb_read_posted_mbx - Wait for message notification and receive message
191  *  @hw: pointer to the HW structure
192  *  @msg: The message buffer
193  *  @size: Length of buffer
194  *  @mbx_id: id of mailbox to write
195  *
196  *  returns SUCCESS if it successfully received a message notification and
197  *  copied it into the receive buffer.
198  **/
199 static s32 igb_read_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size, 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, u16 mbx_id)
226 {
227 	struct e1000_mbx_info *mbx = &hw->mbx;
228 	s32 ret_val = -E1000_ERR_MBX;
229 
230 	/* exit if either we can't write or there isn't a defined timeout */
231 	if (!mbx->ops.write || !mbx->timeout)
232 		goto out;
233 
234 	/* send msg */
235 	ret_val = mbx->ops.write(hw, msg, size, mbx_id);
236 
237 	/* if msg sent wait until we receive an ack */
238 	if (!ret_val)
239 		ret_val = igb_poll_for_ack(hw, mbx_id);
240 out:
241 	return ret_val;
242 }
243 
244 static s32 igb_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
245 {
246 	u32 mbvficr = rd32(E1000_MBVFICR);
247 	s32 ret_val = -E1000_ERR_MBX;
248 
249 	if (mbvficr & mask) {
250 		ret_val = 0;
251 		wr32(E1000_MBVFICR, mask);
252 	}
253 
254 	return ret_val;
255 }
256 
257 /**
258  *  igb_check_for_msg_pf - checks to see if the VF has sent mail
259  *  @hw: pointer to the HW structure
260  *  @vf_number: the VF index
261  *
262  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
263  **/
264 static s32 igb_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
265 {
266 	s32 ret_val = -E1000_ERR_MBX;
267 
268 	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
269 		ret_val = 0;
270 		hw->mbx.stats.reqs++;
271 	}
272 
273 	return ret_val;
274 }
275 
276 /**
277  *  igb_check_for_ack_pf - checks to see if the VF has ACKed
278  *  @hw: pointer to the HW structure
279  *  @vf_number: the VF index
280  *
281  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
282  **/
283 static s32 igb_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
284 {
285 	s32 ret_val = -E1000_ERR_MBX;
286 
287 	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
288 		ret_val = 0;
289 		hw->mbx.stats.acks++;
290 	}
291 
292 	return ret_val;
293 }
294 
295 /**
296  *  igb_check_for_rst_pf - checks to see if the VF has reset
297  *  @hw: pointer to the HW structure
298  *  @vf_number: the VF index
299  *
300  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
301  **/
302 static s32 igb_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
303 {
304 	u32 vflre = rd32(E1000_VFLRE);
305 	s32 ret_val = -E1000_ERR_MBX;
306 
307 	if (vflre & (1 << vf_number)) {
308 		ret_val = 0;
309 		wr32(E1000_VFLRE, (1 << vf_number));
310 		hw->mbx.stats.rsts++;
311 	}
312 
313 	return ret_val;
314 }
315 
316 /**
317  *  igb_obtain_mbx_lock_pf - obtain mailbox lock
318  *  @hw: pointer to the HW structure
319  *  @vf_number: the VF index
320  *
321  *  return SUCCESS if we obtained the mailbox lock
322  **/
323 static s32 igb_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
324 {
325 	s32 ret_val = -E1000_ERR_MBX;
326 	u32 p2v_mailbox;
327 
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