1/*******************************************************************************
2
3  Intel 10 Gigabit PCI Express Linux driver
4  Copyright(c) 1999 - 2012 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 <linux/pci.h>
29#include <linux/delay.h>
30#include "ixgbe_type.h"
31#include "ixgbe_common.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 **/
43s32 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 **/
67s32 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 **/
88s32 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 **/
106s32 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 **/
124s32 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 **/
142static 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
157out:
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 **/
168static 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
183out:
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 **/
197static 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);
211out:
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 **/
225static 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);
241out:
242	return ret_val;
243}
244
245static 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 **/
265static 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 **/
287static 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 **/
309static 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 **/
343static 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 **/
368static 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
393out_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 **/
409static 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
430out_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 */
441void 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
462struct 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