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 **/
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
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 **/
66s32 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 **/
86s32 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 **/
103s32 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 **/
120s32 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 **/
137static 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 **/
162static 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 **/
190static 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 **/
217static 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
236static 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 **/
255static 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 **/
276static 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 **/
297static 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 **/
332static 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 **/
356static 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 **/
395static 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 */
426void 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
449struct 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