1 /*******************************************************************************
2 
3   Intel 10 Gigabit PCI Express Linux driver
4   Copyright(c) 1999 - 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   Linux NICS <linux.nics@intel.com>
24   e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
25   Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
26 
27 *******************************************************************************/
28 
29 #include <linux/pci.h>
30 #include <linux/delay.h>
31 #include "ixgbe.h"
32 #include "ixgbe_mbx.h"
33 
34 /**
35  *  ixgbe_read_mbx - Reads a message from the mailbox
36  *  @hw: pointer to the HW structure
37  *  @msg: The message buffer
38  *  @size: Length of buffer
39  *  @mbx_id: id of mailbox to read
40  *
41  *  returns SUCCESS if it successfully read message from buffer
42  **/
43 s32 ixgbe_read_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size, u16 mbx_id)
44 {
45 	struct ixgbe_mbx_info *mbx = &hw->mbx;
46 	s32 ret_val = IXGBE_ERR_MBX;
47 
48 	/* limit read to size of mailbox */
49 	if (size > mbx->size)
50 		size = mbx->size;
51 
52 	if (mbx->ops.read)
53 		ret_val = mbx->ops.read(hw, msg, size, mbx_id);
54 
55 	return ret_val;
56 }
57 
58 /**
59  *  ixgbe_write_mbx - Write a message to the mailbox
60  *  @hw: pointer to the HW structure
61  *  @msg: The message buffer
62  *  @size: Length of buffer
63  *  @mbx_id: id of mailbox to write
64  *
65  *  returns SUCCESS if it successfully copied message into the buffer
66  **/
67 s32 ixgbe_write_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size, u16 mbx_id)
68 {
69 	struct ixgbe_mbx_info *mbx = &hw->mbx;
70 	s32 ret_val = 0;
71 
72 	if (size > mbx->size)
73 		ret_val = IXGBE_ERR_MBX;
74 
75 	else if (mbx->ops.write)
76 		ret_val = mbx->ops.write(hw, msg, size, mbx_id);
77 
78 	return ret_val;
79 }
80 
81 /**
82  *  ixgbe_check_for_msg - checks to see if someone sent us mail
83  *  @hw: pointer to the HW structure
84  *  @mbx_id: id of mailbox to check
85  *
86  *  returns SUCCESS if the Status bit was found or else ERR_MBX
87  **/
88 s32 ixgbe_check_for_msg(struct ixgbe_hw *hw, u16 mbx_id)
89 {
90 	struct ixgbe_mbx_info *mbx = &hw->mbx;
91 	s32 ret_val = IXGBE_ERR_MBX;
92 
93 	if (mbx->ops.check_for_msg)
94 		ret_val = mbx->ops.check_for_msg(hw, mbx_id);
95 
96 	return ret_val;
97 }
98 
99 /**
100  *  ixgbe_check_for_ack - checks to see if someone sent us ACK
101  *  @hw: pointer to the HW structure
102  *  @mbx_id: id of mailbox to check
103  *
104  *  returns SUCCESS if the Status bit was found or else ERR_MBX
105  **/
106 s32 ixgbe_check_for_ack(struct ixgbe_hw *hw, u16 mbx_id)
107 {
108 	struct ixgbe_mbx_info *mbx = &hw->mbx;
109 	s32 ret_val = IXGBE_ERR_MBX;
110 
111 	if (mbx->ops.check_for_ack)
112 		ret_val = mbx->ops.check_for_ack(hw, mbx_id);
113 
114 	return ret_val;
115 }
116 
117 /**
118  *  ixgbe_check_for_rst - checks to see if other side has reset
119  *  @hw: pointer to the HW structure
120  *  @mbx_id: id of mailbox to check
121  *
122  *  returns SUCCESS if the Status bit was found or else ERR_MBX
123  **/
124 s32 ixgbe_check_for_rst(struct ixgbe_hw *hw, u16 mbx_id)
125 {
126 	struct ixgbe_mbx_info *mbx = &hw->mbx;
127 	s32 ret_val = IXGBE_ERR_MBX;
128 
129 	if (mbx->ops.check_for_rst)
130 		ret_val = mbx->ops.check_for_rst(hw, mbx_id);
131 
132 	return ret_val;
133 }
134 
135 /**
136  *  ixgbe_poll_for_msg - Wait for message notification
137  *  @hw: pointer to the HW structure
138  *  @mbx_id: id of mailbox to write
139  *
140  *  returns SUCCESS if it successfully received a message notification
141  **/
142 static s32 ixgbe_poll_for_msg(struct ixgbe_hw *hw, u16 mbx_id)
143 {
144 	struct ixgbe_mbx_info *mbx = &hw->mbx;
145 	int countdown = mbx->timeout;
146 
147 	if (!countdown || !mbx->ops.check_for_msg)
148 		goto out;
149 
150 	while (countdown && mbx->ops.check_for_msg(hw, mbx_id)) {
151 		countdown--;
152 		if (!countdown)
153 			break;
154 		udelay(mbx->usec_delay);
155 	}
156 
157 out:
158 	return countdown ? 0 : IXGBE_ERR_MBX;
159 }
160 
161 /**
162  *  ixgbe_poll_for_ack - Wait for message acknowledgement
163  *  @hw: pointer to the HW structure
164  *  @mbx_id: id of mailbox to write
165  *
166  *  returns SUCCESS if it successfully received a message acknowledgement
167  **/
168 static s32 ixgbe_poll_for_ack(struct ixgbe_hw *hw, u16 mbx_id)
169 {
170 	struct ixgbe_mbx_info *mbx = &hw->mbx;
171 	int countdown = mbx->timeout;
172 
173 	if (!countdown || !mbx->ops.check_for_ack)
174 		goto out;
175 
176 	while (countdown && mbx->ops.check_for_ack(hw, mbx_id)) {
177 		countdown--;
178 		if (!countdown)
179 			break;
180 		udelay(mbx->usec_delay);
181 	}
182 
183 out:
184 	return countdown ? 0 : IXGBE_ERR_MBX;
185 }
186 
187 /**
188  *  ixgbe_read_posted_mbx - Wait for message notification and receive message
189  *  @hw: pointer to the HW structure
190  *  @msg: The message buffer
191  *  @size: Length of buffer
192  *  @mbx_id: id of mailbox to write
193  *
194  *  returns SUCCESS if it successfully received a message notification and
195  *  copied it into the receive buffer.
196  **/
197 static s32 ixgbe_read_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size,
198 				 u16 mbx_id)
199 {
200 	struct ixgbe_mbx_info *mbx = &hw->mbx;
201 	s32 ret_val = IXGBE_ERR_MBX;
202 
203 	if (!mbx->ops.read)
204 		goto out;
205 
206 	ret_val = ixgbe_poll_for_msg(hw, mbx_id);
207 
208 	/* if ack received read message, otherwise we timed out */
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  *  ixgbe_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 ixgbe_write_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size,
226 			   u16 mbx_id)
227 {
228 	struct ixgbe_mbx_info *mbx = &hw->mbx;
229 	s32 ret_val = IXGBE_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 = ixgbe_poll_for_ack(hw, mbx_id);
241 out:
242 	return ret_val;
243 }
244 
245 static s32 ixgbe_check_for_bit_pf(struct ixgbe_hw *hw, u32 mask, s32 index)
246 {
247 	u32 mbvficr = IXGBE_READ_REG(hw, IXGBE_MBVFICR(index));
248 	s32 ret_val = IXGBE_ERR_MBX;
249 
250 	if (mbvficr & mask) {
251 		ret_val = 0;
252 		IXGBE_WRITE_REG(hw, IXGBE_MBVFICR(index), mask);
253 	}
254 
255 	return ret_val;
256 }
257 
258 /**
259  *  ixgbe_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 ixgbe_check_for_msg_pf(struct ixgbe_hw *hw, u16 vf_number)
266 {
267 	s32 ret_val = IXGBE_ERR_MBX;
268 	s32 index = IXGBE_MBVFICR_INDEX(vf_number);
269 	u32 vf_bit = vf_number % 16;
270 
271 	if (!ixgbe_check_for_bit_pf(hw, IXGBE_MBVFICR_VFREQ_VF1 << vf_bit,
272 				    index)) {
273 		ret_val = 0;
274 		hw->mbx.stats.reqs++;
275 	}
276 
277 	return ret_val;
278 }
279 
280 /**
281  *  ixgbe_check_for_ack_pf - checks to see if the VF has ACKed
282  *  @hw: pointer to the HW structure
283  *  @vf_number: the VF index
284  *
285  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
286  **/
287 static s32 ixgbe_check_for_ack_pf(struct ixgbe_hw *hw, u16 vf_number)
288 {
289 	s32 ret_val = IXGBE_ERR_MBX;
290 	s32 index = IXGBE_MBVFICR_INDEX(vf_number);
291 	u32 vf_bit = vf_number % 16;
292 
293 	if (!ixgbe_check_for_bit_pf(hw, IXGBE_MBVFICR_VFACK_VF1 << vf_bit,
294 				    index)) {
295 		ret_val = 0;
296 		hw->mbx.stats.acks++;
297 	}
298 
299 	return ret_val;
300 }
301 
302 /**
303  *  ixgbe_check_for_rst_pf - checks to see if the VF has reset
304  *  @hw: pointer to the HW structure
305  *  @vf_number: the VF index
306  *
307  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
308  **/
309 static s32 ixgbe_check_for_rst_pf(struct ixgbe_hw *hw, u16 vf_number)
310 {
311 	u32 reg_offset = (vf_number < 32) ? 0 : 1;
312 	u32 vf_shift = vf_number % 32;
313 	u32 vflre = 0;
314 	s32 ret_val = IXGBE_ERR_MBX;
315 
316 	switch (hw->mac.type) {
317 	case ixgbe_mac_82599EB:
318 		vflre = IXGBE_READ_REG(hw, IXGBE_VFLRE(reg_offset));
319 		break;
320 	case ixgbe_mac_X540:
321 		vflre = IXGBE_READ_REG(hw, IXGBE_VFLREC(reg_offset));
322 		break;
323 	default:
324 		break;
325 	}
326 
327 	if (vflre & (1 << vf_shift)) {
328 		ret_val = 0;
329 		IXGBE_WRITE_REG(hw, IXGBE_VFLREC(reg_offset), (1 << vf_shift));
330 		hw->mbx.stats.rsts++;
331 	}
332 
333 	return ret_val;
334 }
335 
336 /**
337  *  ixgbe_obtain_mbx_lock_pf - obtain mailbox lock
338  *  @hw: pointer to the HW structure
339  *  @vf_number: the VF index
340  *
341  *  return SUCCESS if we obtained the mailbox lock
342  **/
343 static s32 ixgbe_obtain_mbx_lock_pf(struct ixgbe_hw *hw, u16 vf_number)
344 {
345 	s32 ret_val = IXGBE_ERR_MBX;
346 	u32 p2v_mailbox;
347 
348 	/* Take ownership of the buffer */
349 	IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_PFU);
350 
351 	/* reserve mailbox for vf use */
352 	p2v_mailbox = IXGBE_READ_REG(hw, IXGBE_PFMAILBOX(vf_number));
353 	if (p2v_mailbox & IXGBE_PFMAILBOX_PFU)
354 		ret_val = 0;
355 
356 	return ret_val;
357 }
358 
359 /**
360  *  ixgbe_write_mbx_pf - Places a message in the mailbox
361  *  @hw: pointer to the HW structure
362  *  @msg: The message buffer
363  *  @size: Length of buffer
364  *  @vf_number: the VF index
365  *
366  *  returns SUCCESS if it successfully copied message into the buffer
367  **/
368 static s32 ixgbe_write_mbx_pf(struct ixgbe_hw *hw, u32 *msg, u16 size,
369 			      u16 vf_number)
370 {
371 	s32 ret_val;
372 	u16 i;
373 
374 	/* lock the mailbox to prevent pf/vf race condition */
375 	ret_val = ixgbe_obtain_mbx_lock_pf(hw, vf_number);
376 	if (ret_val)
377 		goto out_no_write;
378 
379 	/* flush msg and acks as we are overwriting the message buffer */
380 	ixgbe_check_for_msg_pf(hw, vf_number);
381 	ixgbe_check_for_ack_pf(hw, vf_number);
382 
383 	/* copy the caller specified message to the mailbox memory buffer */
384 	for (i = 0; i < size; i++)
385 		IXGBE_WRITE_REG_ARRAY(hw, IXGBE_PFMBMEM(vf_number), i, msg[i]);
386 
387 	/* Interrupt VF to tell it a message has been sent and release buffer*/
388 	IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_STS);
389 
390 	/* update stats */
391 	hw->mbx.stats.msgs_tx++;
392 
393 out_no_write:
394 	return ret_val;
395 
396 }
397 
398 /**
399  *  ixgbe_read_mbx_pf - Read a message from the mailbox
400  *  @hw: pointer to the HW structure
401  *  @msg: The message buffer
402  *  @size: Length of buffer
403  *  @vf_number: the VF index
404  *
405  *  This function copies a message from the mailbox buffer to the caller's
406  *  memory buffer.  The presumption is that the caller knows that there was
407  *  a message due to a VF request so no polling for message is needed.
408  **/
409 static s32 ixgbe_read_mbx_pf(struct ixgbe_hw *hw, u32 *msg, u16 size,
410 			     u16 vf_number)
411 {
412 	s32 ret_val;
413 	u16 i;
414 
415 	/* lock the mailbox to prevent pf/vf race condition */
416 	ret_val = ixgbe_obtain_mbx_lock_pf(hw, vf_number);
417 	if (ret_val)
418 		goto out_no_read;
419 
420 	/* copy the message to the mailbox memory buffer */
421 	for (i = 0; i < size; i++)
422 		msg[i] = IXGBE_READ_REG_ARRAY(hw, IXGBE_PFMBMEM(vf_number), i);
423 
424 	/* Acknowledge the message and release buffer */
425 	IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_ACK);
426 
427 	/* update stats */
428 	hw->mbx.stats.msgs_rx++;
429 
430 out_no_read:
431 	return ret_val;
432 }
433 
434 #ifdef CONFIG_PCI_IOV
435 /**
436  *  ixgbe_init_mbx_params_pf - set initial values for pf mailbox
437  *  @hw: pointer to the HW structure
438  *
439  *  Initializes the hw->mbx struct to correct values for pf mailbox
440  */
441 void ixgbe_init_mbx_params_pf(struct ixgbe_hw *hw)
442 {
443 	struct ixgbe_mbx_info *mbx = &hw->mbx;
444 
445 	if (hw->mac.type != ixgbe_mac_82599EB &&
446 	    hw->mac.type != ixgbe_mac_X540)
447 		return;
448 
449 	mbx->timeout = 0;
450 	mbx->usec_delay = 0;
451 
452 	mbx->stats.msgs_tx = 0;
453 	mbx->stats.msgs_rx = 0;
454 	mbx->stats.reqs = 0;
455 	mbx->stats.acks = 0;
456 	mbx->stats.rsts = 0;
457 
458 	mbx->size = IXGBE_VFMAILBOX_SIZE;
459 }
460 #endif /* CONFIG_PCI_IOV */
461 
462 struct ixgbe_mbx_operations mbx_ops_generic = {
463 	.read                   = ixgbe_read_mbx_pf,
464 	.write                  = ixgbe_write_mbx_pf,
465 	.read_posted            = ixgbe_read_posted_mbx,
466 	.write_posted           = ixgbe_write_posted_mbx,
467 	.check_for_msg          = ixgbe_check_for_msg_pf,
468 	.check_for_ack          = ixgbe_check_for_ack_pf,
469 	.check_for_rst          = ixgbe_check_for_rst_pf,
470 };
471 
472