1 /*******************************************************************************
2 
3   Intel 10 Gigabit PCI Express Linux driver
4   Copyright(c) 1999 - 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, 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 
47 	/* limit read to size of mailbox */
48 	if (size > mbx->size)
49 		size = mbx->size;
50 
51 	if (!mbx->ops.read)
52 		return IXGBE_ERR_MBX;
53 
54 	return mbx->ops.read(hw, msg, size, mbx_id);
55 }
56 
57 /**
58  *  ixgbe_write_mbx - Write a message to the mailbox
59  *  @hw: pointer to the HW structure
60  *  @msg: The message buffer
61  *  @size: Length of buffer
62  *  @mbx_id: id of mailbox to write
63  *
64  *  returns SUCCESS if it successfully copied message into the buffer
65  **/
66 s32 ixgbe_write_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size, u16 mbx_id)
67 {
68 	struct ixgbe_mbx_info *mbx = &hw->mbx;
69 
70 	if (size > mbx->size)
71 		return IXGBE_ERR_MBX;
72 
73 	if (!mbx->ops.write)
74 		return IXGBE_ERR_MBX;
75 
76 	return mbx->ops.write(hw, msg, size, mbx_id);
77 }
78 
79 /**
80  *  ixgbe_check_for_msg - checks to see if someone sent us mail
81  *  @hw: pointer to the HW structure
82  *  @mbx_id: id of mailbox to check
83  *
84  *  returns SUCCESS if the Status bit was found or else ERR_MBX
85  **/
86 s32 ixgbe_check_for_msg(struct ixgbe_hw *hw, u16 mbx_id)
87 {
88 	struct ixgbe_mbx_info *mbx = &hw->mbx;
89 
90 	if (!mbx->ops.check_for_msg)
91 		return IXGBE_ERR_MBX;
92 
93 	return mbx->ops.check_for_msg(hw, mbx_id);
94 }
95 
96 /**
97  *  ixgbe_check_for_ack - checks to see if someone sent us ACK
98  *  @hw: pointer to the HW structure
99  *  @mbx_id: id of mailbox to check
100  *
101  *  returns SUCCESS if the Status bit was found or else ERR_MBX
102  **/
103 s32 ixgbe_check_for_ack(struct ixgbe_hw *hw, u16 mbx_id)
104 {
105 	struct ixgbe_mbx_info *mbx = &hw->mbx;
106 
107 	if (!mbx->ops.check_for_ack)
108 		return IXGBE_ERR_MBX;
109 
110 	return mbx->ops.check_for_ack(hw, mbx_id);
111 }
112 
113 /**
114  *  ixgbe_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 ixgbe_check_for_rst(struct ixgbe_hw *hw, u16 mbx_id)
121 {
122 	struct ixgbe_mbx_info *mbx = &hw->mbx;
123 
124 	if (!mbx->ops.check_for_rst)
125 		return IXGBE_ERR_MBX;
126 
127 	return mbx->ops.check_for_rst(hw, mbx_id);
128 }
129 
130 /**
131  *  ixgbe_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 ixgbe_poll_for_msg(struct ixgbe_hw *hw, u16 mbx_id)
138 {
139 	struct ixgbe_mbx_info *mbx = &hw->mbx;
140 	int countdown = mbx->timeout;
141 
142 	if (!countdown || !mbx->ops.check_for_msg)
143 		return IXGBE_ERR_MBX;
144 
145 	while (mbx->ops.check_for_msg(hw, mbx_id)) {
146 		countdown--;
147 		if (!countdown)
148 			return IXGBE_ERR_MBX;
149 		udelay(mbx->usec_delay);
150 	}
151 
152 	return 0;
153 }
154 
155 /**
156  *  ixgbe_poll_for_ack - Wait for message acknowledgement
157  *  @hw: pointer to the HW structure
158  *  @mbx_id: id of mailbox to write
159  *
160  *  returns SUCCESS if it successfully received a message acknowledgement
161  **/
162 static s32 ixgbe_poll_for_ack(struct ixgbe_hw *hw, u16 mbx_id)
163 {
164 	struct ixgbe_mbx_info *mbx = &hw->mbx;
165 	int countdown = mbx->timeout;
166 
167 	if (!countdown || !mbx->ops.check_for_ack)
168 		return IXGBE_ERR_MBX;
169 
170 	while (mbx->ops.check_for_ack(hw, mbx_id)) {
171 		countdown--;
172 		if (!countdown)
173 			return IXGBE_ERR_MBX;
174 		udelay(mbx->usec_delay);
175 	}
176 
177 	return 0;
178 }
179 
180 /**
181  *  ixgbe_read_posted_mbx - Wait for message notification and receive message
182  *  @hw: pointer to the HW structure
183  *  @msg: The message buffer
184  *  @size: Length of buffer
185  *  @mbx_id: id of mailbox to write
186  *
187  *  returns SUCCESS if it successfully received a message notification and
188  *  copied it into the receive buffer.
189  **/
190 static s32 ixgbe_read_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size,
191 				 u16 mbx_id)
192 {
193 	struct ixgbe_mbx_info *mbx = &hw->mbx;
194 	s32 ret_val;
195 
196 	if (!mbx->ops.read)
197 		return IXGBE_ERR_MBX;
198 
199 	ret_val = ixgbe_poll_for_msg(hw, mbx_id);
200 	if (ret_val)
201 		return ret_val;
202 
203 	/* if ack received read message */
204 	return mbx->ops.read(hw, msg, size, mbx_id);
205 }
206 
207 /**
208  *  ixgbe_write_posted_mbx - Write a message to the mailbox, wait for ack
209  *  @hw: pointer to the HW structure
210  *  @msg: The message buffer
211  *  @size: Length of buffer
212  *  @mbx_id: id of mailbox to write
213  *
214  *  returns SUCCESS if it successfully copied message into the buffer and
215  *  received an ack to that message within delay * timeout period
216  **/
217 static s32 ixgbe_write_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size,
218 			   u16 mbx_id)
219 {
220 	struct ixgbe_mbx_info *mbx = &hw->mbx;
221 	s32 ret_val;
222 
223 	/* exit if either we can't write or there isn't a defined timeout */
224 	if (!mbx->ops.write || !mbx->timeout)
225 		return IXGBE_ERR_MBX;
226 
227 	/* send msg */
228 	ret_val = mbx->ops.write(hw, msg, size, mbx_id);
229 	if (ret_val)
230 		return ret_val;
231 
232 	/* if msg sent wait until we receive an ack */
233 	return ixgbe_poll_for_ack(hw, mbx_id);
234 }
235 
236 static s32 ixgbe_check_for_bit_pf(struct ixgbe_hw *hw, u32 mask, s32 index)
237 {
238 	u32 mbvficr = IXGBE_READ_REG(hw, IXGBE_MBVFICR(index));
239 
240 	if (mbvficr & mask) {
241 		IXGBE_WRITE_REG(hw, IXGBE_MBVFICR(index), mask);
242 		return 0;
243 	}
244 
245 	return IXGBE_ERR_MBX;
246 }
247 
248 /**
249  *  ixgbe_check_for_msg_pf - checks to see if the VF has sent mail
250  *  @hw: pointer to the HW structure
251  *  @vf_number: the VF index
252  *
253  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
254  **/
255 static s32 ixgbe_check_for_msg_pf(struct ixgbe_hw *hw, u16 vf_number)
256 {
257 	s32 index = IXGBE_MBVFICR_INDEX(vf_number);
258 	u32 vf_bit = vf_number % 16;
259 
260 	if (!ixgbe_check_for_bit_pf(hw, IXGBE_MBVFICR_VFREQ_VF1 << vf_bit,
261 				    index)) {
262 		hw->mbx.stats.reqs++;
263 		return 0;
264 	}
265 
266 	return IXGBE_ERR_MBX;
267 }
268 
269 /**
270  *  ixgbe_check_for_ack_pf - checks to see if the VF has ACKed
271  *  @hw: pointer to the HW structure
272  *  @vf_number: the VF index
273  *
274  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
275  **/
276 static s32 ixgbe_check_for_ack_pf(struct ixgbe_hw *hw, u16 vf_number)
277 {
278 	s32 index = IXGBE_MBVFICR_INDEX(vf_number);
279 	u32 vf_bit = vf_number % 16;
280 
281 	if (!ixgbe_check_for_bit_pf(hw, IXGBE_MBVFICR_VFACK_VF1 << vf_bit,
282 				    index)) {
283 		hw->mbx.stats.acks++;
284 		return 0;
285 	}
286 
287 	return IXGBE_ERR_MBX;
288 }
289 
290 /**
291  *  ixgbe_check_for_rst_pf - checks to see if the VF has reset
292  *  @hw: pointer to the HW structure
293  *  @vf_number: the VF index
294  *
295  *  returns SUCCESS if the VF has set the Status bit or else ERR_MBX
296  **/
297 static s32 ixgbe_check_for_rst_pf(struct ixgbe_hw *hw, u16 vf_number)
298 {
299 	u32 reg_offset = (vf_number < 32) ? 0 : 1;
300 	u32 vf_shift = vf_number % 32;
301 	u32 vflre = 0;
302 
303 	switch (hw->mac.type) {
304 	case ixgbe_mac_82599EB:
305 		vflre = IXGBE_READ_REG(hw, IXGBE_VFLRE(reg_offset));
306 		break;
307 	case ixgbe_mac_X540:
308 	case ixgbe_mac_X550:
309 	case ixgbe_mac_X550EM_x:
310 		vflre = IXGBE_READ_REG(hw, IXGBE_VFLREC(reg_offset));
311 		break;
312 	default:
313 		break;
314 	}
315 
316 	if (vflre & (1 << vf_shift)) {
317 		IXGBE_WRITE_REG(hw, IXGBE_VFLREC(reg_offset), (1 << vf_shift));
318 		hw->mbx.stats.rsts++;
319 		return 0;
320 	}
321 
322 	return IXGBE_ERR_MBX;
323 }
324 
325 /**
326  *  ixgbe_obtain_mbx_lock_pf - obtain mailbox lock
327  *  @hw: pointer to the HW structure
328  *  @vf_number: the VF index
329  *
330  *  return SUCCESS if we obtained the mailbox lock
331  **/
332 static s32 ixgbe_obtain_mbx_lock_pf(struct ixgbe_hw *hw, u16 vf_number)
333 {
334 	u32 p2v_mailbox;
335 
336 	/* Take ownership of the buffer */
337 	IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_PFU);
338 
339 	/* reserve mailbox for vf use */
340 	p2v_mailbox = IXGBE_READ_REG(hw, IXGBE_PFMAILBOX(vf_number));
341 	if (p2v_mailbox & IXGBE_PFMAILBOX_PFU)
342 		return 0;
343 
344 	return IXGBE_ERR_MBX;
345 }
346 
347 /**
348  *  ixgbe_write_mbx_pf - Places a message in the mailbox
349  *  @hw: pointer to the HW structure
350  *  @msg: The message buffer
351  *  @size: Length of buffer
352  *  @vf_number: the VF index
353  *
354  *  returns SUCCESS if it successfully copied message into the buffer
355  **/
356 static s32 ixgbe_write_mbx_pf(struct ixgbe_hw *hw, u32 *msg, u16 size,
357 			      u16 vf_number)
358 {
359 	s32 ret_val;
360 	u16 i;
361 
362 	/* lock the mailbox to prevent pf/vf race condition */
363 	ret_val = ixgbe_obtain_mbx_lock_pf(hw, vf_number);
364 	if (ret_val)
365 		return ret_val;
366 
367 	/* flush msg and acks as we are overwriting the message buffer */
368 	ixgbe_check_for_msg_pf(hw, vf_number);
369 	ixgbe_check_for_ack_pf(hw, vf_number);
370 
371 	/* copy the caller specified message to the mailbox memory buffer */
372 	for (i = 0; i < size; i++)
373 		IXGBE_WRITE_REG_ARRAY(hw, IXGBE_PFMBMEM(vf_number), i, msg[i]);
374 
375 	/* Interrupt VF to tell it a message has been sent and release buffer*/
376 	IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_STS);
377 
378 	/* update stats */
379 	hw->mbx.stats.msgs_tx++;
380 
381 	return 0;
382 }
383 
384 /**
385  *  ixgbe_read_mbx_pf - Read a message from the mailbox
386  *  @hw: pointer to the HW structure
387  *  @msg: The message buffer
388  *  @size: Length of buffer
389  *  @vf_number: the VF index
390  *
391  *  This function copies a message from the mailbox buffer to the caller's
392  *  memory buffer.  The presumption is that the caller knows that there was
393  *  a message due to a VF request so no polling for message is needed.
394  **/
395 static s32 ixgbe_read_mbx_pf(struct ixgbe_hw *hw, u32 *msg, u16 size,
396 			     u16 vf_number)
397 {
398 	s32 ret_val;
399 	u16 i;
400 
401 	/* lock the mailbox to prevent pf/vf race condition */
402 	ret_val = ixgbe_obtain_mbx_lock_pf(hw, vf_number);
403 	if (ret_val)
404 		return ret_val;
405 
406 	/* copy the message to the mailbox memory buffer */
407 	for (i = 0; i < size; i++)
408 		msg[i] = IXGBE_READ_REG_ARRAY(hw, IXGBE_PFMBMEM(vf_number), i);
409 
410 	/* Acknowledge the message and release buffer */
411 	IXGBE_WRITE_REG(hw, IXGBE_PFMAILBOX(vf_number), IXGBE_PFMAILBOX_ACK);
412 
413 	/* update stats */
414 	hw->mbx.stats.msgs_rx++;
415 
416 	return 0;
417 }
418 
419 #ifdef CONFIG_PCI_IOV
420 /**
421  *  ixgbe_init_mbx_params_pf - set initial values for pf mailbox
422  *  @hw: pointer to the HW structure
423  *
424  *  Initializes the hw->mbx struct to correct values for pf mailbox
425  */
426 void ixgbe_init_mbx_params_pf(struct ixgbe_hw *hw)
427 {
428 	struct ixgbe_mbx_info *mbx = &hw->mbx;
429 
430 	if (hw->mac.type != ixgbe_mac_82599EB &&
431 	    hw->mac.type != ixgbe_mac_X550 &&
432 	    hw->mac.type != ixgbe_mac_X550EM_x &&
433 	    hw->mac.type != ixgbe_mac_X540)
434 		return;
435 
436 	mbx->timeout = 0;
437 	mbx->usec_delay = 0;
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 	mbx->size = IXGBE_VFMAILBOX_SIZE;
446 }
447 #endif /* CONFIG_PCI_IOV */
448 
449 struct ixgbe_mbx_operations mbx_ops_generic = {
450 	.read                   = ixgbe_read_mbx_pf,
451 	.write                  = ixgbe_write_mbx_pf,
452 	.read_posted            = ixgbe_read_posted_mbx,
453 	.write_posted           = ixgbe_write_posted_mbx,
454 	.check_for_msg          = ixgbe_check_for_msg_pf,
455 	.check_for_ack          = ixgbe_check_for_ack_pf,
456 	.check_for_rst          = ixgbe_check_for_rst_pf,
457 };
458 
459