1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3 *
4 * Name: hwsleep.c - ACPI Hardware Sleep/Wake Support functions for the
5 * original/legacy sleep/PM registers.
6 *
7 * Copyright (C) 2000 - 2021, Intel Corp.
8 *
9 *****************************************************************************/
10
11 #include <acpi/acpi.h>
12 #include "accommon.h"
13
14 #define _COMPONENT ACPI_HARDWARE
15 ACPI_MODULE_NAME("hwsleep")
16
17 #if (!ACPI_REDUCED_HARDWARE) /* Entire module */
18 /*******************************************************************************
19 *
20 * FUNCTION: acpi_hw_legacy_sleep
21 *
22 * PARAMETERS: sleep_state - Which sleep state to enter
23 *
24 * RETURN: Status
25 *
26 * DESCRIPTION: Enter a system sleep state via the legacy FADT PM registers
27 * THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
28 *
29 ******************************************************************************/
acpi_hw_legacy_sleep(u8 sleep_state)30 acpi_status acpi_hw_legacy_sleep(u8 sleep_state)
31 {
32 struct acpi_bit_register_info *sleep_type_reg_info;
33 struct acpi_bit_register_info *sleep_enable_reg_info;
34 u32 pm1a_control;
35 u32 pm1b_control;
36 u32 in_value;
37 acpi_status status;
38
39 ACPI_FUNCTION_TRACE(hw_legacy_sleep);
40
41 sleep_type_reg_info =
42 acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
43 sleep_enable_reg_info =
44 acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
45
46 /* Clear wake status */
47
48 status = acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS,
49 ACPI_CLEAR_STATUS);
50 if (ACPI_FAILURE(status)) {
51 return_ACPI_STATUS(status);
52 }
53
54 /* Disable all GPEs */
55 status = acpi_hw_disable_all_gpes();
56 if (ACPI_FAILURE(status)) {
57 return_ACPI_STATUS(status);
58 }
59 status = acpi_hw_clear_acpi_status();
60 if (ACPI_FAILURE(status)) {
61 return_ACPI_STATUS(status);
62 }
63 acpi_gbl_system_awake_and_running = FALSE;
64
65 /* Enable all wakeup GPEs */
66 status = acpi_hw_enable_all_wakeup_gpes();
67 if (ACPI_FAILURE(status)) {
68 return_ACPI_STATUS(status);
69 }
70
71 /* Get current value of PM1A control */
72
73 status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
74 &pm1a_control);
75 if (ACPI_FAILURE(status)) {
76 return_ACPI_STATUS(status);
77 }
78 ACPI_DEBUG_PRINT((ACPI_DB_INIT,
79 "Entering sleep state [S%u]\n", sleep_state));
80
81 /* Clear the SLP_EN and SLP_TYP fields */
82
83 pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
84 sleep_enable_reg_info->access_bit_mask);
85 pm1b_control = pm1a_control;
86
87 /* Insert the SLP_TYP bits */
88
89 pm1a_control |=
90 (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
91 pm1b_control |=
92 (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
93
94 /*
95 * We split the writes of SLP_TYP and SLP_EN to workaround
96 * poorly implemented hardware.
97 */
98
99 /* Write #1: write the SLP_TYP data to the PM1 Control registers */
100
101 status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
102 if (ACPI_FAILURE(status)) {
103 return_ACPI_STATUS(status);
104 }
105
106 /* Insert the sleep enable (SLP_EN) bit */
107
108 pm1a_control |= sleep_enable_reg_info->access_bit_mask;
109 pm1b_control |= sleep_enable_reg_info->access_bit_mask;
110
111 /* Flush caches, as per ACPI specification */
112
113 ACPI_FLUSH_CPU_CACHE();
114
115 status = acpi_os_enter_sleep(sleep_state, pm1a_control, pm1b_control);
116 if (status == AE_CTRL_TERMINATE) {
117 return_ACPI_STATUS(AE_OK);
118 }
119 if (ACPI_FAILURE(status)) {
120 return_ACPI_STATUS(status);
121 }
122
123 /* Write #2: Write both SLP_TYP + SLP_EN */
124
125 status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
126 if (ACPI_FAILURE(status)) {
127 return_ACPI_STATUS(status);
128 }
129
130 if (sleep_state > ACPI_STATE_S3) {
131 /*
132 * We wanted to sleep > S3, but it didn't happen (by virtue of the
133 * fact that we are still executing!)
134 *
135 * Wait ten seconds, then try again. This is to get S4/S5 to work on
136 * all machines.
137 *
138 * We wait so long to allow chipsets that poll this reg very slowly
139 * to still read the right value. Ideally, this block would go
140 * away entirely.
141 */
142 acpi_os_stall(10 * ACPI_USEC_PER_SEC);
143
144 status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
145 sleep_enable_reg_info->
146 access_bit_mask);
147 if (ACPI_FAILURE(status)) {
148 return_ACPI_STATUS(status);
149 }
150 }
151
152 /* Wait for transition back to Working State */
153
154 do {
155 status =
156 acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
157 if (ACPI_FAILURE(status)) {
158 return_ACPI_STATUS(status);
159 }
160
161 } while (!in_value);
162
163 return_ACPI_STATUS(AE_OK);
164 }
165
166 /*******************************************************************************
167 *
168 * FUNCTION: acpi_hw_legacy_wake_prep
169 *
170 * PARAMETERS: sleep_state - Which sleep state we just exited
171 *
172 * RETURN: Status
173 *
174 * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
175 * sleep.
176 * Called with interrupts ENABLED.
177 *
178 ******************************************************************************/
179
acpi_hw_legacy_wake_prep(u8 sleep_state)180 acpi_status acpi_hw_legacy_wake_prep(u8 sleep_state)
181 {
182 acpi_status status = AE_OK;
183 struct acpi_bit_register_info *sleep_type_reg_info;
184 struct acpi_bit_register_info *sleep_enable_reg_info;
185 u32 pm1a_control;
186 u32 pm1b_control;
187
188 ACPI_FUNCTION_TRACE(hw_legacy_wake_prep);
189
190 /*
191 * Set SLP_TYPE and SLP_EN to state S0.
192 * This is unclear from the ACPI Spec, but it is required
193 * by some machines.
194 */
195 if (acpi_gbl_sleep_type_a_s0 != ACPI_SLEEP_TYPE_INVALID) {
196 sleep_type_reg_info =
197 acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
198 sleep_enable_reg_info =
199 acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
200
201 /* Get current value of PM1A control */
202
203 status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
204 &pm1a_control);
205 if (ACPI_SUCCESS(status)) {
206
207 /* Clear the SLP_EN and SLP_TYP fields */
208
209 pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
210 sleep_enable_reg_info->
211 access_bit_mask);
212 pm1b_control = pm1a_control;
213
214 /* Insert the SLP_TYP bits */
215
216 pm1a_control |= (acpi_gbl_sleep_type_a_s0 <<
217 sleep_type_reg_info->bit_position);
218 pm1b_control |= (acpi_gbl_sleep_type_b_s0 <<
219 sleep_type_reg_info->bit_position);
220
221 /* Write the control registers and ignore any errors */
222
223 (void)acpi_hw_write_pm1_control(pm1a_control,
224 pm1b_control);
225 }
226 }
227
228 return_ACPI_STATUS(status);
229 }
230
231 /*******************************************************************************
232 *
233 * FUNCTION: acpi_hw_legacy_wake
234 *
235 * PARAMETERS: sleep_state - Which sleep state we just exited
236 *
237 * RETURN: Status
238 *
239 * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
240 * Called with interrupts ENABLED.
241 *
242 ******************************************************************************/
243
acpi_hw_legacy_wake(u8 sleep_state)244 acpi_status acpi_hw_legacy_wake(u8 sleep_state)
245 {
246 acpi_status status;
247
248 ACPI_FUNCTION_TRACE(hw_legacy_wake);
249
250 /* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
251
252 acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
253 acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);
254
255 /*
256 * GPEs must be enabled before _WAK is called as GPEs
257 * might get fired there
258 *
259 * Restore the GPEs:
260 * 1) Disable all GPEs
261 * 2) Enable all runtime GPEs
262 */
263 status = acpi_hw_disable_all_gpes();
264 if (ACPI_FAILURE(status)) {
265 return_ACPI_STATUS(status);
266 }
267
268 status = acpi_hw_enable_all_runtime_gpes();
269 if (ACPI_FAILURE(status)) {
270 return_ACPI_STATUS(status);
271 }
272
273 /*
274 * Now we can execute _WAK, etc. Some machines require that the GPEs
275 * are enabled before the wake methods are executed.
276 */
277 acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state);
278
279 /*
280 * Some BIOS code assumes that WAK_STS will be cleared on resume
281 * and use it to determine whether the system is rebooting or
282 * resuming. Clear WAK_STS for compatibility.
283 */
284 (void)acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS,
285 ACPI_CLEAR_STATUS);
286 acpi_gbl_system_awake_and_running = TRUE;
287
288 /* Enable power button */
289
290 (void)
291 acpi_write_bit_register(acpi_gbl_fixed_event_info
292 [ACPI_EVENT_POWER_BUTTON].
293 enable_register_id, ACPI_ENABLE_EVENT);
294
295 (void)
296 acpi_write_bit_register(acpi_gbl_fixed_event_info
297 [ACPI_EVENT_POWER_BUTTON].
298 status_register_id, ACPI_CLEAR_STATUS);
299
300 /* Enable sleep button */
301
302 (void)
303 acpi_write_bit_register(acpi_gbl_fixed_event_info
304 [ACPI_EVENT_SLEEP_BUTTON].
305 enable_register_id, ACPI_ENABLE_EVENT);
306
307 (void)
308 acpi_write_bit_register(acpi_gbl_fixed_event_info
309 [ACPI_EVENT_SLEEP_BUTTON].
310 status_register_id, ACPI_CLEAR_STATUS);
311
312 acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
313 return_ACPI_STATUS(status);
314 }
315
316 #endif /* !ACPI_REDUCED_HARDWARE */
317