1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
4 * Name: hwsleep.c - ACPI Hardware Sleep/Wake Support functions for the
5 * original/legacy sleep/PM registers.
7 * Copyright (C) 2000 - 2023, Intel Corp.
9 *****************************************************************************/
11 #include <acpi/acpi.h>
14 #define _COMPONENT ACPI_HARDWARE
15 ACPI_MODULE_NAME("hwsleep")
17 #if (!ACPI_REDUCED_HARDWARE) /* Entire module */
18 /*******************************************************************************
20 * FUNCTION: acpi_hw_legacy_sleep
22 * PARAMETERS: sleep_state - Which sleep state to enter
26 * DESCRIPTION: Enter a system sleep state via the legacy FADT PM registers
27 * THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
29 ******************************************************************************/
30 acpi_status
acpi_hw_legacy_sleep(u8 sleep_state
)
32 struct acpi_bit_register_info
*sleep_type_reg_info
;
33 struct acpi_bit_register_info
*sleep_enable_reg_info
;
39 ACPI_FUNCTION_TRACE(hw_legacy_sleep
);
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
);
46 /* Clear wake status */
48 status
= acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS
,
50 if (ACPI_FAILURE(status
)) {
51 return_ACPI_STATUS(status
);
54 /* Disable all GPEs */
55 status
= acpi_hw_disable_all_gpes();
56 if (ACPI_FAILURE(status
)) {
57 return_ACPI_STATUS(status
);
59 status
= acpi_hw_clear_acpi_status();
60 if (ACPI_FAILURE(status
)) {
61 return_ACPI_STATUS(status
);
63 acpi_gbl_system_awake_and_running
= FALSE
;
65 /* Enable all wakeup GPEs */
66 status
= acpi_hw_enable_all_wakeup_gpes();
67 if (ACPI_FAILURE(status
)) {
68 return_ACPI_STATUS(status
);
71 /* Get current value of PM1A control */
73 status
= acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL
,
75 if (ACPI_FAILURE(status
)) {
76 return_ACPI_STATUS(status
);
78 ACPI_DEBUG_PRINT((ACPI_DB_INIT
,
79 "Entering sleep state [S%u]\n", sleep_state
));
81 /* Clear the SLP_EN and SLP_TYP fields */
83 pm1a_control
&= ~(sleep_type_reg_info
->access_bit_mask
|
84 sleep_enable_reg_info
->access_bit_mask
);
85 pm1b_control
= pm1a_control
;
87 /* Insert the SLP_TYP bits */
90 (acpi_gbl_sleep_type_a
<< sleep_type_reg_info
->bit_position
);
92 (acpi_gbl_sleep_type_b
<< sleep_type_reg_info
->bit_position
);
95 * We split the writes of SLP_TYP and SLP_EN to workaround
96 * poorly implemented hardware.
99 /* Write #1: write the SLP_TYP data to the PM1 Control registers */
101 status
= acpi_hw_write_pm1_control(pm1a_control
, pm1b_control
);
102 if (ACPI_FAILURE(status
)) {
103 return_ACPI_STATUS(status
);
106 /* Insert the sleep enable (SLP_EN) bit */
108 pm1a_control
|= sleep_enable_reg_info
->access_bit_mask
;
109 pm1b_control
|= sleep_enable_reg_info
->access_bit_mask
;
111 /* Flush caches, as per ACPI specification */
113 if (sleep_state
< ACPI_STATE_S4
) {
114 ACPI_FLUSH_CPU_CACHE();
117 status
= acpi_os_enter_sleep(sleep_state
, pm1a_control
, pm1b_control
);
118 if (status
== AE_CTRL_TERMINATE
) {
119 return_ACPI_STATUS(AE_OK
);
121 if (ACPI_FAILURE(status
)) {
122 return_ACPI_STATUS(status
);
125 /* Write #2: Write both SLP_TYP + SLP_EN */
127 status
= acpi_hw_write_pm1_control(pm1a_control
, pm1b_control
);
128 if (ACPI_FAILURE(status
)) {
129 return_ACPI_STATUS(status
);
132 if (sleep_state
> ACPI_STATE_S3
) {
134 * We wanted to sleep > S3, but it didn't happen (by virtue of the
135 * fact that we are still executing!)
137 * Wait ten seconds, then try again. This is to get S4/S5 to work on
140 * We wait so long to allow chipsets that poll this reg very slowly
141 * to still read the right value. Ideally, this block would go
144 acpi_os_stall(10 * ACPI_USEC_PER_SEC
);
146 status
= acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL
,
147 sleep_enable_reg_info
->
149 if (ACPI_FAILURE(status
)) {
150 return_ACPI_STATUS(status
);
154 /* Wait for transition back to Working State */
158 acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS
, &in_value
);
159 if (ACPI_FAILURE(status
)) {
160 return_ACPI_STATUS(status
);
165 return_ACPI_STATUS(AE_OK
);
168 /*******************************************************************************
170 * FUNCTION: acpi_hw_legacy_wake_prep
172 * PARAMETERS: sleep_state - Which sleep state we just exited
176 * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
178 * Called with interrupts ENABLED.
180 ******************************************************************************/
182 acpi_status
acpi_hw_legacy_wake_prep(u8 sleep_state
)
184 acpi_status status
= AE_OK
;
185 struct acpi_bit_register_info
*sleep_type_reg_info
;
186 struct acpi_bit_register_info
*sleep_enable_reg_info
;
190 ACPI_FUNCTION_TRACE(hw_legacy_wake_prep
);
193 * Set SLP_TYPE and SLP_EN to state S0.
194 * This is unclear from the ACPI Spec, but it is required
197 if (acpi_gbl_sleep_type_a_s0
!= ACPI_SLEEP_TYPE_INVALID
) {
198 sleep_type_reg_info
=
199 acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE
);
200 sleep_enable_reg_info
=
201 acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE
);
203 /* Get current value of PM1A control */
205 status
= acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL
,
207 if (ACPI_SUCCESS(status
)) {
209 /* Clear the SLP_EN and SLP_TYP fields */
211 pm1a_control
&= ~(sleep_type_reg_info
->access_bit_mask
|
212 sleep_enable_reg_info
->
214 pm1b_control
= pm1a_control
;
216 /* Insert the SLP_TYP bits */
218 pm1a_control
|= (acpi_gbl_sleep_type_a_s0
<<
219 sleep_type_reg_info
->bit_position
);
220 pm1b_control
|= (acpi_gbl_sleep_type_b_s0
<<
221 sleep_type_reg_info
->bit_position
);
223 /* Write the control registers and ignore any errors */
225 (void)acpi_hw_write_pm1_control(pm1a_control
,
230 return_ACPI_STATUS(status
);
233 /*******************************************************************************
235 * FUNCTION: acpi_hw_legacy_wake
237 * PARAMETERS: sleep_state - Which sleep state we just exited
241 * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
242 * Called with interrupts ENABLED.
244 ******************************************************************************/
246 acpi_status
acpi_hw_legacy_wake(u8 sleep_state
)
250 ACPI_FUNCTION_TRACE(hw_legacy_wake
);
252 /* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
254 acpi_gbl_sleep_type_a
= ACPI_SLEEP_TYPE_INVALID
;
255 acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST
, ACPI_SST_WAKING
);
258 * GPEs must be enabled before _WAK is called as GPEs
259 * might get fired there
262 * 1) Disable all GPEs
263 * 2) Enable all runtime GPEs
265 status
= acpi_hw_disable_all_gpes();
266 if (ACPI_FAILURE(status
)) {
267 return_ACPI_STATUS(status
);
270 status
= acpi_hw_enable_all_runtime_gpes();
271 if (ACPI_FAILURE(status
)) {
272 return_ACPI_STATUS(status
);
276 * Now we can execute _WAK, etc. Some machines require that the GPEs
277 * are enabled before the wake methods are executed.
279 acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK
, sleep_state
);
282 * Some BIOS code assumes that WAK_STS will be cleared on resume
283 * and use it to determine whether the system is rebooting or
284 * resuming. Clear WAK_STS for compatibility.
286 (void)acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS
,
288 acpi_gbl_system_awake_and_running
= TRUE
;
290 /* Enable power button */
293 acpi_write_bit_register(acpi_gbl_fixed_event_info
294 [ACPI_EVENT_POWER_BUTTON
].
295 enable_register_id
, ACPI_ENABLE_EVENT
);
298 acpi_write_bit_register(acpi_gbl_fixed_event_info
299 [ACPI_EVENT_POWER_BUTTON
].
300 status_register_id
, ACPI_CLEAR_STATUS
);
302 /* Enable sleep button */
305 acpi_write_bit_register(acpi_gbl_fixed_event_info
306 [ACPI_EVENT_SLEEP_BUTTON
].
307 enable_register_id
, ACPI_ENABLE_EVENT
);
310 acpi_write_bit_register(acpi_gbl_fixed_event_info
311 [ACPI_EVENT_SLEEP_BUTTON
].
312 status_register_id
, ACPI_CLEAR_STATUS
);
314 acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST
, ACPI_SST_WORKING
);
315 return_ACPI_STATUS(status
);
318 #endif /* !ACPI_REDUCED_HARDWARE */