1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2020-21 Intel Corporation.
4 */
5
6 #include "iosm_ipc_protocol.h"
7
8 /* Timeout value in MS for the PM to wait for device to reach active state */
9 #define IPC_PM_ACTIVE_TIMEOUT_MS (500)
10
11 /* Note that here "active" has the value 1, as compared to the enums
12 * ipc_mem_host_pm_state or ipc_mem_dev_pm_state, where "active" is 0
13 */
14 #define IPC_PM_SLEEP (0)
15 #define CONSUME_STATE (0)
16 #define IPC_PM_ACTIVE (1)
17
ipc_pm_signal_hpda_doorbell(struct iosm_pm * ipc_pm,u32 identifier,bool host_slp_check)18 void ipc_pm_signal_hpda_doorbell(struct iosm_pm *ipc_pm, u32 identifier,
19 bool host_slp_check)
20 {
21 if (host_slp_check && ipc_pm->host_pm_state != IPC_MEM_HOST_PM_ACTIVE &&
22 ipc_pm->host_pm_state != IPC_MEM_HOST_PM_ACTIVE_WAIT) {
23 ipc_pm->pending_hpda_update = true;
24 dev_dbg(ipc_pm->dev,
25 "Pend HPDA update set. Host PM_State: %d identifier:%d",
26 ipc_pm->host_pm_state, identifier);
27 return;
28 }
29
30 if (!ipc_pm_trigger(ipc_pm, IPC_PM_UNIT_IRQ, true)) {
31 ipc_pm->pending_hpda_update = true;
32 dev_dbg(ipc_pm->dev, "Pending HPDA update set. identifier:%d",
33 identifier);
34 return;
35 }
36 ipc_pm->pending_hpda_update = false;
37
38 /* Trigger the irq towards CP */
39 ipc_cp_irq_hpda_update(ipc_pm->pcie, identifier);
40
41 ipc_pm_trigger(ipc_pm, IPC_PM_UNIT_IRQ, false);
42 }
43
44 /* Wake up the device if it is in low power mode. */
ipc_pm_link_activate(struct iosm_pm * ipc_pm)45 static bool ipc_pm_link_activate(struct iosm_pm *ipc_pm)
46 {
47 if (ipc_pm->cp_state == IPC_MEM_DEV_PM_ACTIVE)
48 return true;
49
50 if (ipc_pm->cp_state == IPC_MEM_DEV_PM_SLEEP) {
51 if (ipc_pm->ap_state == IPC_MEM_DEV_PM_SLEEP) {
52 /* Wake up the device. */
53 ipc_cp_irq_sleep_control(ipc_pm->pcie,
54 IPC_MEM_DEV_PM_WAKEUP);
55 ipc_pm->ap_state = IPC_MEM_DEV_PM_ACTIVE_WAIT;
56
57 goto not_active;
58 }
59
60 if (ipc_pm->ap_state == IPC_MEM_DEV_PM_ACTIVE_WAIT)
61 goto not_active;
62
63 return true;
64 }
65
66 not_active:
67 /* link is not ready */
68 return false;
69 }
70
ipc_pm_wait_for_device_active(struct iosm_pm * ipc_pm)71 bool ipc_pm_wait_for_device_active(struct iosm_pm *ipc_pm)
72 {
73 bool ret_val = false;
74
75 if (ipc_pm->ap_state != IPC_MEM_DEV_PM_ACTIVE) {
76 /* Complete all memory stores before setting bit */
77 smp_mb__before_atomic();
78
79 /* Wait for IPC_PM_ACTIVE_TIMEOUT_MS for Device sleep state
80 * machine to enter ACTIVE state.
81 */
82 set_bit(0, &ipc_pm->host_sleep_pend);
83
84 /* Complete all memory stores after setting bit */
85 smp_mb__after_atomic();
86
87 if (!wait_for_completion_interruptible_timeout
88 (&ipc_pm->host_sleep_complete,
89 msecs_to_jiffies(IPC_PM_ACTIVE_TIMEOUT_MS))) {
90 dev_err(ipc_pm->dev,
91 "PM timeout. Expected State:%d. Actual: %d",
92 IPC_MEM_DEV_PM_ACTIVE, ipc_pm->ap_state);
93 goto active_timeout;
94 }
95 }
96
97 ret_val = true;
98 active_timeout:
99 /* Complete all memory stores before clearing bit */
100 smp_mb__before_atomic();
101
102 /* Reset the atomic variable in any case as device sleep
103 * state machine change is no longer of interest.
104 */
105 clear_bit(0, &ipc_pm->host_sleep_pend);
106
107 /* Complete all memory stores after clearing bit */
108 smp_mb__after_atomic();
109
110 return ret_val;
111 }
112
ipc_pm_on_link_sleep(struct iosm_pm * ipc_pm)113 static void ipc_pm_on_link_sleep(struct iosm_pm *ipc_pm)
114 {
115 /* pending sleep ack and all conditions are cleared
116 * -> signal SLEEP__ACK to CP
117 */
118 ipc_pm->cp_state = IPC_MEM_DEV_PM_SLEEP;
119 ipc_pm->ap_state = IPC_MEM_DEV_PM_SLEEP;
120
121 ipc_cp_irq_sleep_control(ipc_pm->pcie, IPC_MEM_DEV_PM_SLEEP);
122 }
123
ipc_pm_on_link_wake(struct iosm_pm * ipc_pm,bool ack)124 static void ipc_pm_on_link_wake(struct iosm_pm *ipc_pm, bool ack)
125 {
126 ipc_pm->ap_state = IPC_MEM_DEV_PM_ACTIVE;
127
128 if (ack) {
129 ipc_pm->cp_state = IPC_MEM_DEV_PM_ACTIVE;
130
131 ipc_cp_irq_sleep_control(ipc_pm->pcie, IPC_MEM_DEV_PM_ACTIVE);
132
133 /* check the consume state !!! */
134 if (test_bit(CONSUME_STATE, &ipc_pm->host_sleep_pend))
135 complete(&ipc_pm->host_sleep_complete);
136 }
137
138 /* Check for pending HPDA update.
139 * Pending HP update could be because of sending message was
140 * put on hold due to Device sleep state or due to TD update
141 * which could be because of Device Sleep and Host Sleep
142 * states.
143 */
144 if (ipc_pm->pending_hpda_update &&
145 ipc_pm->host_pm_state == IPC_MEM_HOST_PM_ACTIVE)
146 ipc_pm_signal_hpda_doorbell(ipc_pm, IPC_HP_PM_TRIGGER, true);
147 }
148
ipc_pm_trigger(struct iosm_pm * ipc_pm,enum ipc_pm_unit unit,bool active)149 bool ipc_pm_trigger(struct iosm_pm *ipc_pm, enum ipc_pm_unit unit, bool active)
150 {
151 union ipc_pm_cond old_cond;
152 union ipc_pm_cond new_cond;
153 bool link_active;
154
155 /* Save the current D3 state. */
156 new_cond = ipc_pm->pm_cond;
157 old_cond = ipc_pm->pm_cond;
158
159 /* Calculate the power state only in the runtime phase. */
160 switch (unit) {
161 case IPC_PM_UNIT_IRQ: /* CP irq */
162 new_cond.irq = active;
163 break;
164
165 case IPC_PM_UNIT_LINK: /* Device link state. */
166 new_cond.link = active;
167 break;
168
169 case IPC_PM_UNIT_HS: /* Host sleep trigger requires Link. */
170 new_cond.hs = active;
171 break;
172
173 default:
174 break;
175 }
176
177 /* Something changed ? */
178 if (old_cond.raw == new_cond.raw) {
179 /* Stay in the current PM state. */
180 link_active = old_cond.link == IPC_PM_ACTIVE;
181 goto ret;
182 }
183
184 ipc_pm->pm_cond = new_cond;
185
186 if (new_cond.link)
187 ipc_pm_on_link_wake(ipc_pm, unit == IPC_PM_UNIT_LINK);
188 else if (unit == IPC_PM_UNIT_LINK)
189 ipc_pm_on_link_sleep(ipc_pm);
190
191 if (old_cond.link == IPC_PM_SLEEP && new_cond.raw) {
192 link_active = ipc_pm_link_activate(ipc_pm);
193 goto ret;
194 }
195
196 link_active = old_cond.link == IPC_PM_ACTIVE;
197
198 ret:
199 return link_active;
200 }
201
ipc_pm_prepare_host_sleep(struct iosm_pm * ipc_pm)202 bool ipc_pm_prepare_host_sleep(struct iosm_pm *ipc_pm)
203 {
204 /* suspend not allowed if host_pm_state is not IPC_MEM_HOST_PM_ACTIVE */
205 if (ipc_pm->host_pm_state != IPC_MEM_HOST_PM_ACTIVE) {
206 dev_err(ipc_pm->dev, "host_pm_state=%d\tExpected to be: %d",
207 ipc_pm->host_pm_state, IPC_MEM_HOST_PM_ACTIVE);
208 return false;
209 }
210
211 ipc_pm->host_pm_state = IPC_MEM_HOST_PM_SLEEP_WAIT_D3;
212
213 return true;
214 }
215
ipc_pm_prepare_host_active(struct iosm_pm * ipc_pm)216 bool ipc_pm_prepare_host_active(struct iosm_pm *ipc_pm)
217 {
218 if (ipc_pm->host_pm_state != IPC_MEM_HOST_PM_SLEEP) {
219 dev_err(ipc_pm->dev, "host_pm_state=%d\tExpected to be: %d",
220 ipc_pm->host_pm_state, IPC_MEM_HOST_PM_SLEEP);
221 return false;
222 }
223
224 /* Sending Sleep Exit message to CP. Update the state */
225 ipc_pm->host_pm_state = IPC_MEM_HOST_PM_ACTIVE_WAIT;
226
227 return true;
228 }
229
ipc_pm_set_s2idle_sleep(struct iosm_pm * ipc_pm,bool sleep)230 void ipc_pm_set_s2idle_sleep(struct iosm_pm *ipc_pm, bool sleep)
231 {
232 if (sleep) {
233 ipc_pm->ap_state = IPC_MEM_DEV_PM_SLEEP;
234 ipc_pm->cp_state = IPC_MEM_DEV_PM_SLEEP;
235 ipc_pm->device_sleep_notification = IPC_MEM_DEV_PM_SLEEP;
236 } else {
237 ipc_pm->ap_state = IPC_MEM_DEV_PM_ACTIVE;
238 ipc_pm->cp_state = IPC_MEM_DEV_PM_ACTIVE;
239 ipc_pm->device_sleep_notification = IPC_MEM_DEV_PM_ACTIVE;
240 ipc_pm->pm_cond.link = IPC_PM_ACTIVE;
241 }
242 }
243
ipc_pm_dev_slp_notification(struct iosm_pm * ipc_pm,u32 cp_pm_req)244 bool ipc_pm_dev_slp_notification(struct iosm_pm *ipc_pm, u32 cp_pm_req)
245 {
246 if (cp_pm_req == ipc_pm->device_sleep_notification)
247 return false;
248
249 ipc_pm->device_sleep_notification = cp_pm_req;
250
251 /* Evaluate the PM request. */
252 switch (ipc_pm->cp_state) {
253 case IPC_MEM_DEV_PM_ACTIVE:
254 switch (cp_pm_req) {
255 case IPC_MEM_DEV_PM_ACTIVE:
256 break;
257
258 case IPC_MEM_DEV_PM_SLEEP:
259 /* Inform the PM that the device link can go down. */
260 ipc_pm_trigger(ipc_pm, IPC_PM_UNIT_LINK, false);
261 return true;
262
263 default:
264 dev_err(ipc_pm->dev,
265 "loc-pm=%d active: confused req-pm=%d",
266 ipc_pm->cp_state, cp_pm_req);
267 break;
268 }
269 break;
270
271 case IPC_MEM_DEV_PM_SLEEP:
272 switch (cp_pm_req) {
273 case IPC_MEM_DEV_PM_ACTIVE:
274 /* Inform the PM that the device link is active. */
275 ipc_pm_trigger(ipc_pm, IPC_PM_UNIT_LINK, true);
276 break;
277
278 case IPC_MEM_DEV_PM_SLEEP:
279 break;
280
281 default:
282 dev_err(ipc_pm->dev,
283 "loc-pm=%d sleep: confused req-pm=%d",
284 ipc_pm->cp_state, cp_pm_req);
285 break;
286 }
287 break;
288
289 default:
290 dev_err(ipc_pm->dev, "confused loc-pm=%d, req-pm=%d",
291 ipc_pm->cp_state, cp_pm_req);
292 break;
293 }
294
295 return false;
296 }
297
ipc_pm_init(struct iosm_protocol * ipc_protocol)298 void ipc_pm_init(struct iosm_protocol *ipc_protocol)
299 {
300 struct iosm_imem *ipc_imem = ipc_protocol->imem;
301 struct iosm_pm *ipc_pm = &ipc_protocol->pm;
302
303 ipc_pm->pcie = ipc_imem->pcie;
304 ipc_pm->dev = ipc_imem->dev;
305
306 ipc_pm->pm_cond.irq = IPC_PM_SLEEP;
307 ipc_pm->pm_cond.hs = IPC_PM_SLEEP;
308 ipc_pm->pm_cond.link = IPC_PM_ACTIVE;
309
310 ipc_pm->cp_state = IPC_MEM_DEV_PM_ACTIVE;
311 ipc_pm->ap_state = IPC_MEM_DEV_PM_ACTIVE;
312 ipc_pm->host_pm_state = IPC_MEM_HOST_PM_ACTIVE;
313
314 /* Create generic wait-for-completion handler for Host Sleep
315 * and device sleep coordination.
316 */
317 init_completion(&ipc_pm->host_sleep_complete);
318
319 /* Complete all memory stores before clearing bit */
320 smp_mb__before_atomic();
321
322 clear_bit(0, &ipc_pm->host_sleep_pend);
323
324 /* Complete all memory stores after clearing bit */
325 smp_mb__after_atomic();
326 }
327
ipc_pm_deinit(struct iosm_protocol * proto)328 void ipc_pm_deinit(struct iosm_protocol *proto)
329 {
330 struct iosm_pm *ipc_pm = &proto->pm;
331
332 complete(&ipc_pm->host_sleep_complete);
333 }
334