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 - 2020, Intel Corp.
8 *
9 *****************************************************************************/
10
11#include <acpi/acpi.h>
12#include "accommon.h"
13
14#define _COMPONENT          ACPI_HARDWARE
15ACPI_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 ******************************************************************************/
30acpi_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	if (sleep_state < ACPI_STATE_S4) {
114		ACPI_FLUSH_CPU_CACHE();
115	}
116
117	status = acpi_os_enter_sleep(sleep_state, pm1a_control, pm1b_control);
118	if (status == AE_CTRL_TERMINATE) {
119		return_ACPI_STATUS(AE_OK);
120	}
121	if (ACPI_FAILURE(status)) {
122		return_ACPI_STATUS(status);
123	}
124
125	/* Write #2: Write both SLP_TYP + SLP_EN */
126
127	status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
128	if (ACPI_FAILURE(status)) {
129		return_ACPI_STATUS(status);
130	}
131
132	if (sleep_state > ACPI_STATE_S3) {
133		/*
134		 * We wanted to sleep > S3, but it didn't happen (by virtue of the
135		 * fact that we are still executing!)
136		 *
137		 * Wait ten seconds, then try again. This is to get S4/S5 to work on
138		 * all machines.
139		 *
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
142		 * away entirely.
143		 */
144		acpi_os_stall(10 * ACPI_USEC_PER_SEC);
145
146		status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
147						sleep_enable_reg_info->
148						access_bit_mask);
149		if (ACPI_FAILURE(status)) {
150			return_ACPI_STATUS(status);
151		}
152	}
153
154	/* Wait for transition back to Working State */
155
156	do {
157		status =
158		    acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
159		if (ACPI_FAILURE(status)) {
160			return_ACPI_STATUS(status);
161		}
162
163	} while (!in_value);
164
165	return_ACPI_STATUS(AE_OK);
166}
167
168/*******************************************************************************
169 *
170 * FUNCTION:    acpi_hw_legacy_wake_prep
171 *
172 * PARAMETERS:  sleep_state         - Which sleep state we just exited
173 *
174 * RETURN:      Status
175 *
176 * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
177 *              sleep.
178 *              Called with interrupts ENABLED.
179 *
180 ******************************************************************************/
181
182acpi_status acpi_hw_legacy_wake_prep(u8 sleep_state)
183{
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;
187	u32 pm1a_control;
188	u32 pm1b_control;
189
190	ACPI_FUNCTION_TRACE(hw_legacy_wake_prep);
191
192	/*
193	 * Set SLP_TYPE and SLP_EN to state S0.
194	 * This is unclear from the ACPI Spec, but it is required
195	 * by some machines.
196	 */
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);
202
203		/* Get current value of PM1A control */
204
205		status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
206					       &pm1a_control);
207		if (ACPI_SUCCESS(status)) {
208
209			/* Clear the SLP_EN and SLP_TYP fields */
210
211			pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
212					  sleep_enable_reg_info->
213					  access_bit_mask);
214			pm1b_control = pm1a_control;
215
216			/* Insert the SLP_TYP bits */
217
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);
222
223			/* Write the control registers and ignore any errors */
224
225			(void)acpi_hw_write_pm1_control(pm1a_control,
226							pm1b_control);
227		}
228	}
229
230	return_ACPI_STATUS(status);
231}
232
233/*******************************************************************************
234 *
235 * FUNCTION:    acpi_hw_legacy_wake
236 *
237 * PARAMETERS:  sleep_state         - Which sleep state we just exited
238 *
239 * RETURN:      Status
240 *
241 * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
242 *              Called with interrupts ENABLED.
243 *
244 ******************************************************************************/
245
246acpi_status acpi_hw_legacy_wake(u8 sleep_state)
247{
248	acpi_status status;
249
250	ACPI_FUNCTION_TRACE(hw_legacy_wake);
251
252	/* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
253
254	acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
255	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);
256
257	/*
258	 * GPEs must be enabled before _WAK is called as GPEs
259	 * might get fired there
260	 *
261	 * Restore the GPEs:
262	 * 1) Disable all GPEs
263	 * 2) Enable all runtime GPEs
264	 */
265	status = acpi_hw_disable_all_gpes();
266	if (ACPI_FAILURE(status)) {
267		return_ACPI_STATUS(status);
268	}
269
270	status = acpi_hw_enable_all_runtime_gpes();
271	if (ACPI_FAILURE(status)) {
272		return_ACPI_STATUS(status);
273	}
274
275	/*
276	 * Now we can execute _WAK, etc. Some machines require that the GPEs
277	 * are enabled before the wake methods are executed.
278	 */
279	acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state);
280
281	/*
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.
285	 */
286	(void)acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS,
287				      ACPI_CLEAR_STATUS);
288	acpi_gbl_system_awake_and_running = TRUE;
289
290	/* Enable power button */
291
292	(void)
293	    acpi_write_bit_register(acpi_gbl_fixed_event_info
294				    [ACPI_EVENT_POWER_BUTTON].
295				    enable_register_id, ACPI_ENABLE_EVENT);
296
297	(void)
298	    acpi_write_bit_register(acpi_gbl_fixed_event_info
299				    [ACPI_EVENT_POWER_BUTTON].
300				    status_register_id, ACPI_CLEAR_STATUS);
301
302	/* Enable sleep button */
303
304	(void)
305	    acpi_write_bit_register(acpi_gbl_fixed_event_info
306				    [ACPI_EVENT_SLEEP_BUTTON].
307				    enable_register_id, ACPI_ENABLE_EVENT);
308
309	(void)
310	    acpi_write_bit_register(acpi_gbl_fixed_event_info
311				    [ACPI_EVENT_SLEEP_BUTTON].
312				    status_register_id, ACPI_CLEAR_STATUS);
313
314	/* Enable pcie wake event if support */
315	if ((acpi_gbl_FADT.flags & ACPI_FADT_PCI_EXPRESS_WAKE)) {
316		(void)
317		acpi_write_bit_register(acpi_gbl_fixed_event_info
318				[ACPI_EVENT_PCIE_WAKE].
319				enable_register_id, ACPI_DISABLE_EVENT);
320		(void)
321		acpi_write_bit_register(acpi_gbl_fixed_event_info
322				[ACPI_EVENT_PCIE_WAKE].
323				status_register_id, ACPI_CLEAR_STATUS);
324	}
325
326	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
327	return_ACPI_STATUS(status);
328}
329
330#endif				/* !ACPI_REDUCED_HARDWARE */
331