1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* Copyright(c) 2009 - 2018 Intel Corporation. */ |
3 | |
4 | #include <linux/bitfield.h> |
5 | #include "mbx.h" |
6 | |
7 | /** |
8 | * e1000_poll_for_msg - Wait for message notification |
9 | * @hw: pointer to the HW structure |
10 | * |
11 | * returns SUCCESS if it successfully received a message notification |
12 | **/ |
13 | static s32 e1000_poll_for_msg(struct e1000_hw *hw) |
14 | { |
15 | struct e1000_mbx_info *mbx = &hw->mbx; |
16 | int countdown = mbx->timeout; |
17 | |
18 | if (!mbx->ops.check_for_msg) |
19 | goto out; |
20 | |
21 | while (countdown && mbx->ops.check_for_msg(hw)) { |
22 | countdown--; |
23 | udelay(mbx->usec_delay); |
24 | } |
25 | |
26 | /* if we failed, all future posted messages fail until reset */ |
27 | if (!countdown) |
28 | mbx->timeout = 0; |
29 | out: |
30 | return countdown ? E1000_SUCCESS : -E1000_ERR_MBX; |
31 | } |
32 | |
33 | /** |
34 | * e1000_poll_for_ack - Wait for message acknowledgment |
35 | * @hw: pointer to the HW structure |
36 | * |
37 | * returns SUCCESS if it successfully received a message acknowledgment |
38 | **/ |
39 | static s32 e1000_poll_for_ack(struct e1000_hw *hw) |
40 | { |
41 | struct e1000_mbx_info *mbx = &hw->mbx; |
42 | int countdown = mbx->timeout; |
43 | |
44 | if (!mbx->ops.check_for_ack) |
45 | goto out; |
46 | |
47 | while (countdown && mbx->ops.check_for_ack(hw)) { |
48 | countdown--; |
49 | udelay(mbx->usec_delay); |
50 | } |
51 | |
52 | /* if we failed, all future posted messages fail until reset */ |
53 | if (!countdown) |
54 | mbx->timeout = 0; |
55 | out: |
56 | return countdown ? E1000_SUCCESS : -E1000_ERR_MBX; |
57 | } |
58 | |
59 | /** |
60 | * e1000_read_posted_mbx - Wait for message notification and receive message |
61 | * @hw: pointer to the HW structure |
62 | * @msg: The message buffer |
63 | * @size: Length of buffer |
64 | * |
65 | * returns SUCCESS if it successfully received a message notification and |
66 | * copied it into the receive buffer. |
67 | **/ |
68 | static s32 e1000_read_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size) |
69 | { |
70 | struct e1000_mbx_info *mbx = &hw->mbx; |
71 | s32 ret_val = -E1000_ERR_MBX; |
72 | |
73 | if (!mbx->ops.read) |
74 | goto out; |
75 | |
76 | ret_val = e1000_poll_for_msg(hw); |
77 | |
78 | /* if ack received read message, otherwise we timed out */ |
79 | if (!ret_val) |
80 | ret_val = mbx->ops.read(hw, msg, size); |
81 | out: |
82 | return ret_val; |
83 | } |
84 | |
85 | /** |
86 | * e1000_write_posted_mbx - Write a message to the mailbox, wait for ack |
87 | * @hw: pointer to the HW structure |
88 | * @msg: The message buffer |
89 | * @size: Length of buffer |
90 | * |
91 | * returns SUCCESS if it successfully copied message into the buffer and |
92 | * received an ack to that message within delay * timeout period |
93 | **/ |
94 | static s32 e1000_write_posted_mbx(struct e1000_hw *hw, u32 *msg, u16 size) |
95 | { |
96 | struct e1000_mbx_info *mbx = &hw->mbx; |
97 | s32 ret_val = -E1000_ERR_MBX; |
98 | |
99 | /* exit if we either can't write or there isn't a defined timeout */ |
100 | if (!mbx->ops.write || !mbx->timeout) |
101 | goto out; |
102 | |
103 | /* send msg*/ |
104 | ret_val = mbx->ops.write(hw, msg, size); |
105 | |
106 | /* if msg sent wait until we receive an ack */ |
107 | if (!ret_val) |
108 | ret_val = e1000_poll_for_ack(hw); |
109 | out: |
110 | return ret_val; |
111 | } |
112 | |
113 | /** |
114 | * e1000_read_v2p_mailbox - read v2p mailbox |
115 | * @hw: pointer to the HW structure |
116 | * |
117 | * This function is used to read the v2p mailbox without losing the read to |
118 | * clear status bits. |
119 | **/ |
120 | static u32 e1000_read_v2p_mailbox(struct e1000_hw *hw) |
121 | { |
122 | u32 v2p_mailbox = er32(V2PMAILBOX(0)); |
123 | |
124 | v2p_mailbox |= hw->dev_spec.vf.v2p_mailbox; |
125 | hw->dev_spec.vf.v2p_mailbox |= v2p_mailbox & E1000_V2PMAILBOX_R2C_BITS; |
126 | |
127 | return v2p_mailbox; |
128 | } |
129 | |
130 | /** |
131 | * e1000_check_for_bit_vf - Determine if a status bit was set |
132 | * @hw: pointer to the HW structure |
133 | * @mask: bitmask for bits to be tested and cleared |
134 | * |
135 | * This function is used to check for the read to clear bits within |
136 | * the V2P mailbox. |
137 | **/ |
138 | static s32 e1000_check_for_bit_vf(struct e1000_hw *hw, u32 mask) |
139 | { |
140 | u32 v2p_mailbox = e1000_read_v2p_mailbox(hw); |
141 | s32 ret_val = -E1000_ERR_MBX; |
142 | |
143 | if (v2p_mailbox & mask) |
144 | ret_val = E1000_SUCCESS; |
145 | |
146 | hw->dev_spec.vf.v2p_mailbox &= ~mask; |
147 | |
148 | return ret_val; |
149 | } |
150 | |
151 | /** |
152 | * e1000_check_for_msg_vf - checks to see if the PF has sent mail |
153 | * @hw: pointer to the HW structure |
154 | * |
155 | * returns SUCCESS if the PF has set the Status bit or else ERR_MBX |
156 | **/ |
157 | static s32 e1000_check_for_msg_vf(struct e1000_hw *hw) |
158 | { |
159 | s32 ret_val = -E1000_ERR_MBX; |
160 | |
161 | if (!e1000_check_for_bit_vf(hw, E1000_V2PMAILBOX_PFSTS)) { |
162 | ret_val = E1000_SUCCESS; |
163 | hw->mbx.stats.reqs++; |
164 | } |
165 | |
166 | return ret_val; |
167 | } |
168 | |
169 | /** |
170 | * e1000_check_for_ack_vf - checks to see if the PF has ACK'd |
171 | * @hw: pointer to the HW structure |
172 | * |
173 | * returns SUCCESS if the PF has set the ACK bit or else ERR_MBX |
174 | **/ |
175 | static s32 e1000_check_for_ack_vf(struct e1000_hw *hw) |
176 | { |
177 | s32 ret_val = -E1000_ERR_MBX; |
178 | |
179 | if (!e1000_check_for_bit_vf(hw, E1000_V2PMAILBOX_PFACK)) { |
180 | ret_val = E1000_SUCCESS; |
181 | hw->mbx.stats.acks++; |
182 | } |
183 | |
184 | return ret_val; |
185 | } |
186 | |
187 | /** |
188 | * e1000_check_for_rst_vf - checks to see if the PF has reset |
189 | * @hw: pointer to the HW structure |
190 | * |
191 | * returns true if the PF has set the reset done bit or else false |
192 | **/ |
193 | static s32 e1000_check_for_rst_vf(struct e1000_hw *hw) |
194 | { |
195 | s32 ret_val = -E1000_ERR_MBX; |
196 | |
197 | if (!e1000_check_for_bit_vf(hw, mask: (E1000_V2PMAILBOX_RSTD | |
198 | E1000_V2PMAILBOX_RSTI))) { |
199 | ret_val = E1000_SUCCESS; |
200 | hw->mbx.stats.rsts++; |
201 | } |
202 | |
203 | return ret_val; |
204 | } |
205 | |
206 | /** |
207 | * e1000_obtain_mbx_lock_vf - obtain mailbox lock |
208 | * @hw: pointer to the HW structure |
209 | * |
210 | * return SUCCESS if we obtained the mailbox lock |
211 | **/ |
212 | static s32 e1000_obtain_mbx_lock_vf(struct e1000_hw *hw) |
213 | { |
214 | s32 ret_val = -E1000_ERR_MBX; |
215 | int count = 10; |
216 | |
217 | do { |
218 | /* Take ownership of the buffer */ |
219 | ew32(V2PMAILBOX(0), E1000_V2PMAILBOX_VFU); |
220 | |
221 | /* reserve mailbox for VF use */ |
222 | if (e1000_read_v2p_mailbox(hw) & E1000_V2PMAILBOX_VFU) { |
223 | ret_val = 0; |
224 | break; |
225 | } |
226 | udelay(1000); |
227 | } while (count-- > 0); |
228 | |
229 | return ret_val; |
230 | } |
231 | |
232 | /** |
233 | * e1000_write_mbx_vf - Write a message to the mailbox |
234 | * @hw: pointer to the HW structure |
235 | * @msg: The message buffer |
236 | * @size: Length of buffer |
237 | * |
238 | * returns SUCCESS if it successfully copied message into the buffer |
239 | **/ |
240 | static s32 e1000_write_mbx_vf(struct e1000_hw *hw, u32 *msg, u16 size) |
241 | { |
242 | s32 err; |
243 | u16 i; |
244 | |
245 | lockdep_assert_held(&hw->mbx_lock); |
246 | |
247 | /* lock the mailbox to prevent pf/vf race condition */ |
248 | err = e1000_obtain_mbx_lock_vf(hw); |
249 | if (err) |
250 | goto out_no_write; |
251 | |
252 | /* flush any ack or msg as we are going to overwrite mailbox */ |
253 | e1000_check_for_ack_vf(hw); |
254 | e1000_check_for_msg_vf(hw); |
255 | |
256 | /* copy the caller specified message to the mailbox memory buffer */ |
257 | for (i = 0; i < size; i++) |
258 | array_ew32(VMBMEM(0), i, msg[i]); |
259 | |
260 | /* update stats */ |
261 | hw->mbx.stats.msgs_tx++; |
262 | |
263 | /* Drop VFU and interrupt the PF to tell it a message has been sent */ |
264 | ew32(V2PMAILBOX(0), E1000_V2PMAILBOX_REQ); |
265 | |
266 | out_no_write: |
267 | return err; |
268 | } |
269 | |
270 | /** |
271 | * e1000_read_mbx_vf - Reads a message from the inbox intended for VF |
272 | * @hw: pointer to the HW structure |
273 | * @msg: The message buffer |
274 | * @size: Length of buffer |
275 | * |
276 | * returns SUCCESS if it successfully read message from buffer |
277 | **/ |
278 | static s32 e1000_read_mbx_vf(struct e1000_hw *hw, u32 *msg, u16 size) |
279 | { |
280 | s32 err; |
281 | u16 i; |
282 | |
283 | lockdep_assert_held(&hw->mbx_lock); |
284 | |
285 | /* lock the mailbox to prevent pf/vf race condition */ |
286 | err = e1000_obtain_mbx_lock_vf(hw); |
287 | if (err) |
288 | goto out_no_read; |
289 | |
290 | /* copy the message from the mailbox memory buffer */ |
291 | for (i = 0; i < size; i++) |
292 | msg[i] = array_er32(VMBMEM(0), i); |
293 | |
294 | /* Acknowledge receipt and release mailbox, then we're done */ |
295 | ew32(V2PMAILBOX(0), E1000_V2PMAILBOX_ACK); |
296 | |
297 | /* update stats */ |
298 | hw->mbx.stats.msgs_rx++; |
299 | |
300 | out_no_read: |
301 | return err; |
302 | } |
303 | |
304 | /** |
305 | * e1000_init_mbx_params_vf - set initial values for VF mailbox |
306 | * @hw: pointer to the HW structure |
307 | * |
308 | * Initializes the hw->mbx struct to correct values for VF mailbox |
309 | */ |
310 | s32 e1000_init_mbx_params_vf(struct e1000_hw *hw) |
311 | { |
312 | struct e1000_mbx_info *mbx = &hw->mbx; |
313 | |
314 | /* start mailbox as timed out and let the reset_hw call set the timeout |
315 | * value to being communications |
316 | */ |
317 | mbx->timeout = 0; |
318 | mbx->usec_delay = E1000_VF_MBX_INIT_DELAY; |
319 | |
320 | mbx->size = E1000_VFMAILBOX_SIZE; |
321 | |
322 | mbx->ops.read = e1000_read_mbx_vf; |
323 | mbx->ops.write = e1000_write_mbx_vf; |
324 | mbx->ops.read_posted = e1000_read_posted_mbx; |
325 | mbx->ops.write_posted = e1000_write_posted_mbx; |
326 | mbx->ops.check_for_msg = e1000_check_for_msg_vf; |
327 | mbx->ops.check_for_ack = e1000_check_for_ack_vf; |
328 | mbx->ops.check_for_rst = e1000_check_for_rst_vf; |
329 | |
330 | mbx->stats.msgs_tx = 0; |
331 | mbx->stats.msgs_rx = 0; |
332 | mbx->stats.reqs = 0; |
333 | mbx->stats.acks = 0; |
334 | mbx->stats.rsts = 0; |
335 | |
336 | return E1000_SUCCESS; |
337 | } |
338 | |