1 /*******************************************************************************
2 
3   Intel 82599 Virtual Function 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 "mbx.h"
29 #include "ixgbevf.h"
30 
31 /**
32  *  ixgbevf_poll_for_msg - Wait for message notification
33  *  @hw: pointer to the HW structure
34  *
35  *  returns 0 if it successfully received a message notification
36  **/
37 static s32 ixgbevf_poll_for_msg(struct ixgbe_hw *hw)
38 {
39 	struct ixgbe_mbx_info *mbx = &hw->mbx;
40 	int countdown = mbx->timeout;
41 
42 	while (countdown && mbx->ops.check_for_msg(hw)) {
43 		countdown--;
44 		udelay(mbx->udelay);
45 	}
46 
47 	/* if we failed, all future posted messages fail until reset */
48 	if (!countdown)
49 		mbx->timeout = 0;
50 
51 	return countdown ? 0 : IXGBE_ERR_MBX;
52 }
53 
54 /**
55  *  ixgbevf_poll_for_ack - Wait for message acknowledgement
56  *  @hw: pointer to the HW structure
57  *
58  *  returns 0 if it successfully received a message acknowledgement
59  **/
60 static s32 ixgbevf_poll_for_ack(struct ixgbe_hw *hw)
61 {
62 	struct ixgbe_mbx_info *mbx = &hw->mbx;
63 	int countdown = mbx->timeout;
64 
65 	while (countdown && mbx->ops.check_for_ack(hw)) {
66 		countdown--;
67 		udelay(mbx->udelay);
68 	}
69 
70 	/* if we failed, all future posted messages fail until reset */
71 	if (!countdown)
72 		mbx->timeout = 0;
73 
74 	return countdown ? 0 : IXGBE_ERR_MBX;
75 }
76 
77 /**
78  *  ixgbevf_read_posted_mbx - Wait for message notification and receive message
79  *  @hw: pointer to the HW structure
80  *  @msg: The message buffer
81  *  @size: Length of buffer
82  *
83  *  returns 0 if it successfully received a message notification and
84  *  copied it into the receive buffer.
85  **/
86 static s32 ixgbevf_read_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size)
87 {
88 	struct ixgbe_mbx_info *mbx = &hw->mbx;
89 	s32 ret_val = IXGBE_ERR_MBX;
90 
91 	ret_val = ixgbevf_poll_for_msg(hw);
92 
93 	/* if ack received read message, otherwise we timed out */
94 	if (!ret_val)
95 		ret_val = mbx->ops.read(hw, msg, size);
96 
97 	return ret_val;
98 }
99 
100 /**
101  *  ixgbevf_write_posted_mbx - Write a message to the mailbox, wait for ack
102  *  @hw: pointer to the HW structure
103  *  @msg: The message buffer
104  *  @size: Length of buffer
105  *
106  *  returns 0 if it successfully copied message into the buffer and
107  *  received an ack to that message within delay * timeout period
108  **/
109 static s32 ixgbevf_write_posted_mbx(struct ixgbe_hw *hw, u32 *msg, u16 size)
110 {
111 	struct ixgbe_mbx_info *mbx = &hw->mbx;
112 	s32 ret_val;
113 
114 	/* send msg */
115 	ret_val = mbx->ops.write(hw, msg, size);
116 
117 	/* if msg sent wait until we receive an ack */
118 	if (!ret_val)
119 		ret_val = ixgbevf_poll_for_ack(hw);
120 
121 	return ret_val;
122 }
123 
124 /**
125  *  ixgbevf_read_v2p_mailbox - read v2p mailbox
126  *  @hw: pointer to the HW structure
127  *
128  *  This function is used to read the v2p mailbox without losing the read to
129  *  clear status bits.
130  **/
131 static u32 ixgbevf_read_v2p_mailbox(struct ixgbe_hw *hw)
132 {
133 	u32 v2p_mailbox = IXGBE_READ_REG(hw, IXGBE_VFMAILBOX);
134 
135 	v2p_mailbox |= hw->mbx.v2p_mailbox;
136 	hw->mbx.v2p_mailbox |= v2p_mailbox & IXGBE_VFMAILBOX_R2C_BITS;
137 
138 	return v2p_mailbox;
139 }
140 
141 /**
142  *  ixgbevf_check_for_bit_vf - Determine if a status bit was set
143  *  @hw: pointer to the HW structure
144  *  @mask: bitmask for bits to be tested and cleared
145  *
146  *  This function is used to check for the read to clear bits within
147  *  the V2P mailbox.
148  **/
149 static s32 ixgbevf_check_for_bit_vf(struct ixgbe_hw *hw, u32 mask)
150 {
151 	u32 v2p_mailbox = ixgbevf_read_v2p_mailbox(hw);
152 	s32 ret_val = IXGBE_ERR_MBX;
153 
154 	if (v2p_mailbox & mask)
155 		ret_val = 0;
156 
157 	hw->mbx.v2p_mailbox &= ~mask;
158 
159 	return ret_val;
160 }
161 
162 /**
163  *  ixgbevf_check_for_msg_vf - checks to see if the PF has sent mail
164  *  @hw: pointer to the HW structure
165  *
166  *  returns 0 if the PF has set the Status bit or else ERR_MBX
167  **/
168 static s32 ixgbevf_check_for_msg_vf(struct ixgbe_hw *hw)
169 {
170 	s32 ret_val = IXGBE_ERR_MBX;
171 
172 	if (!ixgbevf_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFSTS)) {
173 		ret_val = 0;
174 		hw->mbx.stats.reqs++;
175 	}
176 
177 	return ret_val;
178 }
179 
180 /**
181  *  ixgbevf_check_for_ack_vf - checks to see if the PF has ACK'd
182  *  @hw: pointer to the HW structure
183  *
184  *  returns 0 if the PF has set the ACK bit or else ERR_MBX
185  **/
186 static s32 ixgbevf_check_for_ack_vf(struct ixgbe_hw *hw)
187 {
188 	s32 ret_val = IXGBE_ERR_MBX;
189 
190 	if (!ixgbevf_check_for_bit_vf(hw, IXGBE_VFMAILBOX_PFACK)) {
191 		ret_val = 0;
192 		hw->mbx.stats.acks++;
193 	}
194 
195 	return ret_val;
196 }
197 
198 /**
199  *  ixgbevf_check_for_rst_vf - checks to see if the PF has reset
200  *  @hw: pointer to the HW structure
201  *
202  *  returns true if the PF has set the reset done bit or else false
203  **/
204 static s32 ixgbevf_check_for_rst_vf(struct ixgbe_hw *hw)
205 {
206 	s32 ret_val = IXGBE_ERR_MBX;
207 
208 	if (!ixgbevf_check_for_bit_vf(hw, (IXGBE_VFMAILBOX_RSTD |
209 					 IXGBE_VFMAILBOX_RSTI))) {
210 		ret_val = 0;
211 		hw->mbx.stats.rsts++;
212 	}
213 
214 	return ret_val;
215 }
216 
217 /**
218  *  ixgbevf_obtain_mbx_lock_vf - obtain mailbox lock
219  *  @hw: pointer to the HW structure
220  *
221  *  return 0 if we obtained the mailbox lock
222  **/
223 static s32 ixgbevf_obtain_mbx_lock_vf(struct ixgbe_hw *hw)
224 {
225 	s32 ret_val = IXGBE_ERR_MBX;
226 
227 	/* Take ownership of the buffer */
228 	IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_VFU);
229 
230 	/* reserve mailbox for vf use */
231 	if (ixgbevf_read_v2p_mailbox(hw) & IXGBE_VFMAILBOX_VFU)
232 		ret_val = 0;
233 
234 	return ret_val;
235 }
236 
237 /**
238  *  ixgbevf_write_mbx_vf - Write a message to the mailbox
239  *  @hw: pointer to the HW structure
240  *  @msg: The message buffer
241  *  @size: Length of buffer
242  *
243  *  returns 0 if it successfully copied message into the buffer
244  **/
245 static s32 ixgbevf_write_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size)
246 {
247 	s32 ret_val;
248 	u16 i;
249 
250 
251 	/* lock the mailbox to prevent pf/vf race condition */
252 	ret_val = ixgbevf_obtain_mbx_lock_vf(hw);
253 	if (ret_val)
254 		goto out_no_write;
255 
256 	/* flush msg and acks as we are overwriting the message buffer */
257 	ixgbevf_check_for_msg_vf(hw);
258 	ixgbevf_check_for_ack_vf(hw);
259 
260 	/* copy the caller specified message to the mailbox memory buffer */
261 	for (i = 0; i < size; i++)
262 		IXGBE_WRITE_REG_ARRAY(hw, IXGBE_VFMBMEM, i, msg[i]);
263 
264 	/* update stats */
265 	hw->mbx.stats.msgs_tx++;
266 
267 	/* Drop VFU and interrupt the PF to tell it a message has been sent */
268 	IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_REQ);
269 
270 out_no_write:
271 	return ret_val;
272 }
273 
274 /**
275  *  ixgbevf_read_mbx_vf - Reads a message from the inbox intended for vf
276  *  @hw: pointer to the HW structure
277  *  @msg: The message buffer
278  *  @size: Length of buffer
279  *
280  *  returns 0 if it successfully read message from buffer
281  **/
282 static s32 ixgbevf_read_mbx_vf(struct ixgbe_hw *hw, u32 *msg, u16 size)
283 {
284 	s32 ret_val = 0;
285 	u16 i;
286 
287 	/* lock the mailbox to prevent pf/vf race condition */
288 	ret_val = ixgbevf_obtain_mbx_lock_vf(hw);
289 	if (ret_val)
290 		goto out_no_read;
291 
292 	/* copy the message from the mailbox memory buffer */
293 	for (i = 0; i < size; i++)
294 		msg[i] = IXGBE_READ_REG_ARRAY(hw, IXGBE_VFMBMEM, i);
295 
296 	/* Acknowledge receipt and release mailbox, then we're done */
297 	IXGBE_WRITE_REG(hw, IXGBE_VFMAILBOX, IXGBE_VFMAILBOX_ACK);
298 
299 	/* update stats */
300 	hw->mbx.stats.msgs_rx++;
301 
302 out_no_read:
303 	return ret_val;
304 }
305 
306 /**
307  *  ixgbevf_init_mbx_params_vf - set initial values for vf mailbox
308  *  @hw: pointer to the HW structure
309  *
310  *  Initializes the hw->mbx struct to correct values for vf mailbox
311  */
312 static s32 ixgbevf_init_mbx_params_vf(struct ixgbe_hw *hw)
313 {
314 	struct ixgbe_mbx_info *mbx = &hw->mbx;
315 
316 	/* start mailbox as timed out and let the reset_hw call set the timeout
317 	 * value to begin communications */
318 	mbx->timeout = 0;
319 	mbx->udelay = IXGBE_VF_MBX_INIT_DELAY;
320 
321 	mbx->size = IXGBE_VFMAILBOX_SIZE;
322 
323 	mbx->stats.msgs_tx = 0;
324 	mbx->stats.msgs_rx = 0;
325 	mbx->stats.reqs = 0;
326 	mbx->stats.acks = 0;
327 	mbx->stats.rsts = 0;
328 
329 	return 0;
330 }
331 
332 const struct ixgbe_mbx_operations ixgbevf_mbx_ops = {
333 	.init_params   = ixgbevf_init_mbx_params_vf,
334 	.read          = ixgbevf_read_mbx_vf,
335 	.write         = ixgbevf_write_mbx_vf,
336 	.read_posted   = ixgbevf_read_posted_mbx,
337 	.write_posted  = ixgbevf_write_posted_mbx,
338 	.check_for_msg = ixgbevf_check_for_msg_vf,
339 	.check_for_ack = ixgbevf_check_for_ack_vf,
340 	.check_for_rst = ixgbevf_check_for_rst_vf,
341 };
342 
343