xref: /linux/drivers/net/ethernet/intel/igb/e1000_mbx.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
1 /*******************************************************************************
2 
3   Intel(R) Gigabit Ethernet Linux driver
4   Copyright(c) 2007-2013 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 successfully 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,
200 			       u16 mbx_id)
201 {
202 	struct e1000_mbx_info *mbx = &hw->mbx;
203 	s32 ret_val = -E1000_ERR_MBX;
204 
205 	if (!mbx->ops.read)
206 		goto out;
207 
208 	ret_val = igb_poll_for_msg(hw, mbx_id);
209 
210 	if (!ret_val)
211 		ret_val = mbx->ops.read(hw, msg, size, mbx_id);
212 out:
213 	return ret_val;
214 }
215 
216 /**
217  *  igb_write_posted_mbx - Write a message to the mailbox, wait for ack
218  *  @hw: pointer to the HW structure
219  *  @msg: The message buffer
220  *  @size: Length of buffer
221  *  @mbx_id: id of mailbox to write
222  *
223  *  returns SUCCESS if it successfully copied message into the buffer and
224  *  received an ack to that message within delay * timeout period
225  **/
226 static s32 igb_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size,
227 				u16 mbx_id)
228 {
229 	struct e1000_mbx_info *mbx = &hw->mbx;
230 	s32 ret_val = -E1000_ERR_MBX;
231 
232 	/* exit if either we can't write or there isn't a defined timeout */
233 	if (!mbx->ops.write || !mbx->timeout)
234 		goto out;
235 
236 	/* send msg */
237 	ret_val = mbx->ops.write(hw, msg, size, mbx_id);
238 
239 	/* if msg sent wait until we receive an ack */
240 	if (!ret_val)
241 		ret_val = igb_poll_for_ack(hw, mbx_id);
242 out:
243 	return ret_val;
244 }
245 
246 static s32 igb_check_for_bit_pf(struct e1000_hw *hw, u32 mask)
247 {
248 	u32 mbvficr = rd32(E1000_MBVFICR);
249 	s32 ret_val = -E1000_ERR_MBX;
250 
251 	if (mbvficr & mask) {
252 		ret_val = 0;
253 		wr32(E1000_MBVFICR, mask);
254 	}
255 
256 	return ret_val;
257 }
258 
259 /**
260  *  igb_check_for_msg_pf - checks to see if the VF has sent mail
261  *  @hw: pointer to the HW structure
262  *  @vf_number: the VF index
263  *
264  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
265  **/
266 static s32 igb_check_for_msg_pf(struct e1000_hw *hw, u16 vf_number)
267 {
268 	s32 ret_val = -E1000_ERR_MBX;
269 
270 	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFREQ_VF1 << vf_number)) {
271 		ret_val = 0;
272 		hw->mbx.stats.reqs++;
273 	}
274 
275 	return ret_val;
276 }
277 
278 /**
279  *  igb_check_for_ack_pf - checks to see if the VF has ACKed
280  *  @hw: pointer to the HW structure
281  *  @vf_number: the VF index
282  *
283  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
284  **/
285 static s32 igb_check_for_ack_pf(struct e1000_hw *hw, u16 vf_number)
286 {
287 	s32 ret_val = -E1000_ERR_MBX;
288 
289 	if (!igb_check_for_bit_pf(hw, E1000_MBVFICR_VFACK_VF1 << vf_number)) {
290 		ret_val = 0;
291 		hw->mbx.stats.acks++;
292 	}
293 
294 	return ret_val;
295 }
296 
297 /**
298  *  igb_check_for_rst_pf - checks to see if the VF has reset
299  *  @hw: pointer to the HW structure
300  *  @vf_number: the VF index
301  *
302  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
303  **/
304 static s32 igb_check_for_rst_pf(struct e1000_hw *hw, u16 vf_number)
305 {
306 	u32 vflre = rd32(E1000_VFLRE);
307 	s32 ret_val = -E1000_ERR_MBX;
308 
309 	if (vflre & (1 << vf_number)) {
310 		ret_val = 0;
311 		wr32(E1000_VFLRE, (1 << vf_number));
312 		hw->mbx.stats.rsts++;
313 	}
314 
315 	return ret_val;
316 }
317 
318 /**
319  *  igb_obtain_mbx_lock_pf - obtain mailbox lock
320  *  @hw: pointer to the HW structure
321  *  @vf_number: the VF index
322  *
323  *  return SUCCESS if we obtained the mailbox lock
324  **/
325 static s32 igb_obtain_mbx_lock_pf(struct e1000_hw *hw, u16 vf_number)
326 {
327 	s32 ret_val = -E1000_ERR_MBX;
328 	u32 p2v_mailbox;
329 
330 	/* Take ownership of the buffer */
331 	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_PFU);
332 
333 	/* reserve mailbox for vf use */
334 	p2v_mailbox = rd32(E1000_P2VMAILBOX(vf_number));
335 	if (p2v_mailbox & E1000_P2VMAILBOX_PFU)
336 		ret_val = 0;
337 
338 	return ret_val;
339 }
340 
341 /**
342  *  igb_write_mbx_pf - Places a message in the mailbox
343  *  @hw: pointer to the HW structure
344  *  @msg: The message buffer
345  *  @size: Length of buffer
346  *  @vf_number: the VF index
347  *
348  *  returns SUCCESS if it successfully copied message into the buffer
349  **/
350 static s32 igb_write_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
351 			    u16 vf_number)
352 {
353 	s32 ret_val;
354 	u16 i;
355 
356 	/* lock the mailbox to prevent pf/vf race condition */
357 	ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
358 	if (ret_val)
359 		goto out_no_write;
360 
361 	/* flush msg and acks as we are overwriting the message buffer */
362 	igb_check_for_msg_pf(hw, vf_number);
363 	igb_check_for_ack_pf(hw, vf_number);
364 
365 	/* copy the caller specified message to the mailbox memory buffer */
366 	for (i = 0; i < size; i++)
367 		array_wr32(E1000_VMBMEM(vf_number), i, msg[i]);
368 
369 	/* Interrupt VF to tell it a message has been sent and release buffer*/
370 	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_STS);
371 
372 	/* update stats */
373 	hw->mbx.stats.msgs_tx++;
374 
375 out_no_write:
376 	return ret_val;
377 
378 }
379 
380 /**
381  *  igb_read_mbx_pf - Read a message from the mailbox
382  *  @hw: pointer to the HW structure
383  *  @msg: The message buffer
384  *  @size: Length of buffer
385  *  @vf_number: the VF index
386  *
387  *  This function copies a message from the mailbox buffer to the caller's
388  *  memory buffer.  The presumption is that the caller knows that there was
389  *  a message due to a VF request so no polling for message is needed.
390  **/
391 static s32 igb_read_mbx_pf(struct e1000_hw *hw, u32 *msg, u16 size,
392 			   u16 vf_number)
393 {
394 	s32 ret_val;
395 	u16 i;
396 
397 	/* lock the mailbox to prevent pf/vf race condition */
398 	ret_val = igb_obtain_mbx_lock_pf(hw, vf_number);
399 	if (ret_val)
400 		goto out_no_read;
401 
402 	/* copy the message to the mailbox memory buffer */
403 	for (i = 0; i < size; i++)
404 		msg[i] = array_rd32(E1000_VMBMEM(vf_number), i);
405 
406 	/* Acknowledge the message and release buffer */
407 	wr32(E1000_P2VMAILBOX(vf_number), E1000_P2VMAILBOX_ACK);
408 
409 	/* update stats */
410 	hw->mbx.stats.msgs_rx++;
411 
412 out_no_read:
413 	return ret_val;
414 }
415 
416 /**
417  *  e1000_init_mbx_params_pf - set initial values for pf mailbox
418  *  @hw: pointer to the HW structure
419  *
420  *  Initializes the hw->mbx struct to correct values for pf mailbox
421  */
422 s32 igb_init_mbx_params_pf(struct e1000_hw *hw)
423 {
424 	struct e1000_mbx_info *mbx = &hw->mbx;
425 
426 	mbx->timeout = 0;
427 	mbx->usec_delay = 0;
428 
429 	mbx->size = E1000_VFMAILBOX_SIZE;
430 
431 	mbx->ops.read = igb_read_mbx_pf;
432 	mbx->ops.write = igb_write_mbx_pf;
433 	mbx->ops.read_posted = igb_read_posted_mbx;
434 	mbx->ops.write_posted = igb_write_posted_mbx;
435 	mbx->ops.check_for_msg = igb_check_for_msg_pf;
436 	mbx->ops.check_for_ack = igb_check_for_ack_pf;
437 	mbx->ops.check_for_rst = igb_check_for_rst_pf;
438 
439 	mbx->stats.msgs_tx = 0;
440 	mbx->stats.msgs_rx = 0;
441 	mbx->stats.reqs = 0;
442 	mbx->stats.acks = 0;
443 	mbx->stats.rsts = 0;
444 
445 	return 0;
446 }
447 
448