xref: /openbmc/linux/drivers/acpi/acpica/hwesleep.c (revision 2cf1c348)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Name: hwesleep.c - ACPI Hardware Sleep/Wake Support functions for the
5  *                    extended FADT-V5 sleep 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("hwesleep")
16 
17 /*******************************************************************************
18  *
19  * FUNCTION:    acpi_hw_execute_sleep_method
20  *
21  * PARAMETERS:  method_pathname     - Pathname of method to execute
22  *              integer_argument    - Argument to pass to the method
23  *
24  * RETURN:      None
25  *
26  * DESCRIPTION: Execute a sleep/wake related method with one integer argument
27  *              and no return value.
28  *
29  ******************************************************************************/
30 void acpi_hw_execute_sleep_method(char *method_pathname, u32 integer_argument)
31 {
32 	struct acpi_object_list arg_list;
33 	union acpi_object arg;
34 	acpi_status status;
35 
36 	ACPI_FUNCTION_TRACE(hw_execute_sleep_method);
37 
38 	/* One argument, integer_argument; No return value expected */
39 
40 	arg_list.count = 1;
41 	arg_list.pointer = &arg;
42 	arg.type = ACPI_TYPE_INTEGER;
43 	arg.integer.value = (u64)integer_argument;
44 
45 	status = acpi_evaluate_object(NULL, method_pathname, &arg_list, NULL);
46 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
47 		ACPI_EXCEPTION((AE_INFO, status, "While executing method %s",
48 				method_pathname));
49 	}
50 
51 	return_VOID;
52 }
53 
54 /*******************************************************************************
55  *
56  * FUNCTION:    acpi_hw_extended_sleep
57  *
58  * PARAMETERS:  sleep_state         - Which sleep state to enter
59  *
60  * RETURN:      Status
61  *
62  * DESCRIPTION: Enter a system sleep state via the extended FADT sleep
63  *              registers (V5 FADT).
64  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
65  *
66  ******************************************************************************/
67 
68 acpi_status acpi_hw_extended_sleep(u8 sleep_state)
69 {
70 	acpi_status status;
71 	u8 sleep_control;
72 	u64 sleep_status;
73 
74 	ACPI_FUNCTION_TRACE(hw_extended_sleep);
75 
76 	/* Extended sleep registers must be valid */
77 
78 	if (!acpi_gbl_FADT.sleep_control.address ||
79 	    !acpi_gbl_FADT.sleep_status.address) {
80 		return_ACPI_STATUS(AE_NOT_EXIST);
81 	}
82 
83 	/* Clear wake status (WAK_STS) */
84 
85 	status = acpi_write((u64)ACPI_X_WAKE_STATUS,
86 			    &acpi_gbl_FADT.sleep_status);
87 	if (ACPI_FAILURE(status)) {
88 		return_ACPI_STATUS(status);
89 	}
90 
91 	acpi_gbl_system_awake_and_running = FALSE;
92 
93 	/*
94 	 * Set the SLP_TYP and SLP_EN bits.
95 	 *
96 	 * Note: We only use the first value returned by the \_Sx method
97 	 * (acpi_gbl_sleep_type_a) - As per ACPI specification.
98 	 */
99 	ACPI_DEBUG_PRINT((ACPI_DB_INIT,
100 			  "Entering sleep state [S%u]\n", sleep_state));
101 
102 	sleep_control = ((acpi_gbl_sleep_type_a << ACPI_X_SLEEP_TYPE_POSITION) &
103 			 ACPI_X_SLEEP_TYPE_MASK) | ACPI_X_SLEEP_ENABLE;
104 
105 	/* Flush caches, as per ACPI specification */
106 
107 	if (sleep_state < ACPI_STATE_S4) {
108 		ACPI_FLUSH_CPU_CACHE();
109 	}
110 
111 	status = acpi_os_enter_sleep(sleep_state, sleep_control, 0);
112 	if (status == AE_CTRL_TERMINATE) {
113 		return_ACPI_STATUS(AE_OK);
114 	}
115 	if (ACPI_FAILURE(status)) {
116 		return_ACPI_STATUS(status);
117 	}
118 
119 	status = acpi_write((u64)sleep_control, &acpi_gbl_FADT.sleep_control);
120 	if (ACPI_FAILURE(status)) {
121 		return_ACPI_STATUS(status);
122 	}
123 
124 	/* Wait for transition back to Working State */
125 
126 	do {
127 		status = acpi_read(&sleep_status, &acpi_gbl_FADT.sleep_status);
128 		if (ACPI_FAILURE(status)) {
129 			return_ACPI_STATUS(status);
130 		}
131 
132 	} while (!(((u8)sleep_status) & ACPI_X_WAKE_STATUS));
133 
134 	return_ACPI_STATUS(AE_OK);
135 }
136 
137 /*******************************************************************************
138  *
139  * FUNCTION:    acpi_hw_extended_wake_prep
140  *
141  * PARAMETERS:  sleep_state         - Which sleep state we just exited
142  *
143  * RETURN:      Status
144  *
145  * DESCRIPTION: Perform first part of OS-independent ACPI cleanup after
146  *              a sleep. Called with interrupts ENABLED.
147  *
148  ******************************************************************************/
149 
150 acpi_status acpi_hw_extended_wake_prep(u8 sleep_state)
151 {
152 	u8 sleep_type_value;
153 
154 	ACPI_FUNCTION_TRACE(hw_extended_wake_prep);
155 
156 	if (acpi_gbl_sleep_type_a_s0 != ACPI_SLEEP_TYPE_INVALID) {
157 		sleep_type_value =
158 		    ((acpi_gbl_sleep_type_a_s0 << ACPI_X_SLEEP_TYPE_POSITION) &
159 		     ACPI_X_SLEEP_TYPE_MASK);
160 
161 		(void)acpi_write((u64)(sleep_type_value | ACPI_X_SLEEP_ENABLE),
162 				 &acpi_gbl_FADT.sleep_control);
163 	}
164 
165 	return_ACPI_STATUS(AE_OK);
166 }
167 
168 /*******************************************************************************
169  *
170  * FUNCTION:    acpi_hw_extended_wake
171  *
172  * PARAMETERS:  sleep_state         - Which sleep state we just exited
173  *
174  * RETURN:      Status
175  *
176  * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
177  *              Called with interrupts ENABLED.
178  *
179  ******************************************************************************/
180 
181 acpi_status acpi_hw_extended_wake(u8 sleep_state)
182 {
183 	ACPI_FUNCTION_TRACE(hw_extended_wake);
184 
185 	/* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
186 
187 	acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
188 
189 	/* Execute the wake methods */
190 
191 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);
192 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state);
193 
194 	/*
195 	 * Some BIOS code assumes that WAK_STS will be cleared on resume
196 	 * and use it to determine whether the system is rebooting or
197 	 * resuming. Clear WAK_STS for compatibility.
198 	 */
199 	(void)acpi_write((u64)ACPI_X_WAKE_STATUS, &acpi_gbl_FADT.sleep_status);
200 	acpi_gbl_system_awake_and_running = TRUE;
201 
202 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
203 	return_ACPI_STATUS(AE_OK);
204 }
205