xref: /openbmc/linux/drivers/acpi/acpica/hwsleep.c (revision f3539c12)
1 /******************************************************************************
2  *
3  * Name: hwsleep.c - ACPI Hardware Sleep/Wake Support functions for the
4  *                   original/legacy sleep/PM registers.
5  *
6  *****************************************************************************/
7 
8 /*
9  * Copyright (C) 2000 - 2016, Intel Corp.
10  * All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions, and the following disclaimer,
17  *    without modification.
18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19  *    substantially similar to the "NO WARRANTY" disclaimer below
20  *    ("Disclaimer") and any redistribution must be conditioned upon
21  *    including a substantially similar Disclaimer requirement for further
22  *    binary redistribution.
23  * 3. Neither the names of the above-listed copyright holders nor the names
24  *    of any contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * Alternatively, this software may be distributed under the terms of the
28  * GNU General Public License ("GPL") version 2 as published by the Free
29  * Software Foundation.
30  *
31  * NO WARRANTY
32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42  * POSSIBILITY OF SUCH DAMAGES.
43  */
44 
45 #include <acpi/acpi.h>
46 #include <linux/acpi.h>
47 #include "accommon.h"
48 
49 #define _COMPONENT          ACPI_HARDWARE
50 ACPI_MODULE_NAME("hwsleep")
51 
52 #if (!ACPI_REDUCED_HARDWARE)	/* Entire module */
53 /*******************************************************************************
54  *
55  * FUNCTION:    acpi_hw_legacy_sleep
56  *
57  * PARAMETERS:  sleep_state         - Which sleep state to enter
58  *
59  * RETURN:      Status
60  *
61  * DESCRIPTION: Enter a system sleep state via the legacy FADT PM registers
62  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
63  *
64  ******************************************************************************/
65 acpi_status acpi_hw_legacy_sleep(u8 sleep_state)
66 {
67 	struct acpi_bit_register_info *sleep_type_reg_info;
68 	struct acpi_bit_register_info *sleep_enable_reg_info;
69 	u32 pm1a_control;
70 	u32 pm1b_control;
71 	u32 in_value;
72 	acpi_status status;
73 
74 	ACPI_FUNCTION_TRACE(hw_legacy_sleep);
75 
76 	sleep_type_reg_info =
77 	    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
78 	sleep_enable_reg_info =
79 	    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
80 
81 	/* Clear wake status */
82 
83 	status = acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS,
84 					 ACPI_CLEAR_STATUS);
85 	if (ACPI_FAILURE(status)) {
86 		return_ACPI_STATUS(status);
87 	}
88 
89 	/* Clear all fixed and general purpose status bits */
90 
91 	status = acpi_hw_clear_acpi_status();
92 	if (ACPI_FAILURE(status)) {
93 		return_ACPI_STATUS(status);
94 	}
95 
96 	/*
97 	 * 1) Disable/Clear all GPEs
98 	 * 2) Enable all wakeup GPEs
99 	 */
100 	status = acpi_hw_disable_all_gpes();
101 	if (ACPI_FAILURE(status)) {
102 		return_ACPI_STATUS(status);
103 	}
104 	acpi_gbl_system_awake_and_running = FALSE;
105 
106 	status = acpi_hw_enable_all_wakeup_gpes();
107 	if (ACPI_FAILURE(status)) {
108 		return_ACPI_STATUS(status);
109 	}
110 
111 	/* Get current value of PM1A control */
112 
113 	status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
114 				       &pm1a_control);
115 	if (ACPI_FAILURE(status)) {
116 		return_ACPI_STATUS(status);
117 	}
118 	ACPI_DEBUG_PRINT((ACPI_DB_INIT,
119 			  "Entering sleep state [S%u]\n", sleep_state));
120 
121 	/* Clear the SLP_EN and SLP_TYP fields */
122 
123 	pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
124 			  sleep_enable_reg_info->access_bit_mask);
125 	pm1b_control = pm1a_control;
126 
127 	/* Insert the SLP_TYP bits */
128 
129 	pm1a_control |=
130 	    (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
131 	pm1b_control |=
132 	    (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
133 
134 	/*
135 	 * We split the writes of SLP_TYP and SLP_EN to workaround
136 	 * poorly implemented hardware.
137 	 */
138 
139 	/* Write #1: write the SLP_TYP data to the PM1 Control registers */
140 
141 	status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
142 	if (ACPI_FAILURE(status)) {
143 		return_ACPI_STATUS(status);
144 	}
145 
146 	/* Insert the sleep enable (SLP_EN) bit */
147 
148 	pm1a_control |= sleep_enable_reg_info->access_bit_mask;
149 	pm1b_control |= sleep_enable_reg_info->access_bit_mask;
150 
151 	/* Flush caches, as per ACPI specification */
152 
153 	ACPI_FLUSH_CPU_CACHE();
154 
155 	status = acpi_os_prepare_sleep(sleep_state, pm1a_control,
156 				       pm1b_control);
157 	if (ACPI_SKIP(status))
158 		return_ACPI_STATUS(AE_OK);
159 	if (ACPI_FAILURE(status))
160 		return_ACPI_STATUS(status);
161 	/* Write #2: Write both SLP_TYP + SLP_EN */
162 
163 	status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
164 	if (ACPI_FAILURE(status)) {
165 		return_ACPI_STATUS(status);
166 	}
167 
168 	if (sleep_state > ACPI_STATE_S3) {
169 		/*
170 		 * We wanted to sleep > S3, but it didn't happen (by virtue of the
171 		 * fact that we are still executing!)
172 		 *
173 		 * Wait ten seconds, then try again. This is to get S4/S5 to work on
174 		 * all machines.
175 		 *
176 		 * We wait so long to allow chipsets that poll this reg very slowly
177 		 * to still read the right value. Ideally, this block would go
178 		 * away entirely.
179 		 */
180 		acpi_os_stall(10 * ACPI_USEC_PER_SEC);
181 
182 		status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
183 						sleep_enable_reg_info->
184 						access_bit_mask);
185 		if (ACPI_FAILURE(status)) {
186 			return_ACPI_STATUS(status);
187 		}
188 	}
189 
190 	/* Wait for transition back to Working State */
191 
192 	do {
193 		status =
194 		    acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
195 		if (ACPI_FAILURE(status)) {
196 			return_ACPI_STATUS(status);
197 		}
198 
199 	} while (!in_value);
200 
201 	return_ACPI_STATUS(AE_OK);
202 }
203 
204 /*******************************************************************************
205  *
206  * FUNCTION:    acpi_hw_legacy_wake_prep
207  *
208  * PARAMETERS:  sleep_state         - Which sleep state we just exited
209  *
210  * RETURN:      Status
211  *
212  * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
213  *              sleep.
214  *              Called with interrupts ENABLED.
215  *
216  ******************************************************************************/
217 
218 acpi_status acpi_hw_legacy_wake_prep(u8 sleep_state)
219 {
220 	acpi_status status;
221 	struct acpi_bit_register_info *sleep_type_reg_info;
222 	struct acpi_bit_register_info *sleep_enable_reg_info;
223 	u32 pm1a_control;
224 	u32 pm1b_control;
225 
226 	ACPI_FUNCTION_TRACE(hw_legacy_wake_prep);
227 
228 	/*
229 	 * Set SLP_TYPE and SLP_EN to state S0.
230 	 * This is unclear from the ACPI Spec, but it is required
231 	 * by some machines.
232 	 */
233 	status = acpi_get_sleep_type_data(ACPI_STATE_S0,
234 					  &acpi_gbl_sleep_type_a,
235 					  &acpi_gbl_sleep_type_b);
236 	if (ACPI_SUCCESS(status)) {
237 		sleep_type_reg_info =
238 		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
239 		sleep_enable_reg_info =
240 		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
241 
242 		/* Get current value of PM1A control */
243 
244 		status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
245 					       &pm1a_control);
246 		if (ACPI_SUCCESS(status)) {
247 
248 			/* Clear the SLP_EN and SLP_TYP fields */
249 
250 			pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
251 					  sleep_enable_reg_info->
252 					  access_bit_mask);
253 			pm1b_control = pm1a_control;
254 
255 			/* Insert the SLP_TYP bits */
256 
257 			pm1a_control |= (acpi_gbl_sleep_type_a <<
258 					 sleep_type_reg_info->bit_position);
259 			pm1b_control |= (acpi_gbl_sleep_type_b <<
260 					 sleep_type_reg_info->bit_position);
261 
262 			/* Write the control registers and ignore any errors */
263 
264 			(void)acpi_hw_write_pm1_control(pm1a_control,
265 							pm1b_control);
266 		}
267 	}
268 
269 	return_ACPI_STATUS(status);
270 }
271 
272 /*******************************************************************************
273  *
274  * FUNCTION:    acpi_hw_legacy_wake
275  *
276  * PARAMETERS:  sleep_state         - Which sleep state we just exited
277  *
278  * RETURN:      Status
279  *
280  * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
281  *              Called with interrupts ENABLED.
282  *
283  ******************************************************************************/
284 
285 acpi_status acpi_hw_legacy_wake(u8 sleep_state)
286 {
287 	acpi_status status;
288 
289 	ACPI_FUNCTION_TRACE(hw_legacy_wake);
290 
291 	/* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
292 
293 	acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
294 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);
295 
296 	/*
297 	 * GPEs must be enabled before _WAK is called as GPEs
298 	 * might get fired there
299 	 *
300 	 * Restore the GPEs:
301 	 * 1) Disable/Clear all GPEs
302 	 * 2) Enable all runtime GPEs
303 	 */
304 	status = acpi_hw_disable_all_gpes();
305 	if (ACPI_FAILURE(status)) {
306 		return_ACPI_STATUS(status);
307 	}
308 
309 	status = acpi_hw_enable_all_runtime_gpes();
310 	if (ACPI_FAILURE(status)) {
311 		return_ACPI_STATUS(status);
312 	}
313 
314 	/*
315 	 * Now we can execute _WAK, etc. Some machines require that the GPEs
316 	 * are enabled before the wake methods are executed.
317 	 */
318 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state);
319 
320 	/*
321 	 * Some BIOS code assumes that WAK_STS will be cleared on resume
322 	 * and use it to determine whether the system is rebooting or
323 	 * resuming. Clear WAK_STS for compatibility.
324 	 */
325 	(void)acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS,
326 				      ACPI_CLEAR_STATUS);
327 	acpi_gbl_system_awake_and_running = TRUE;
328 
329 	/* Enable power button */
330 
331 	(void)
332 	    acpi_write_bit_register(acpi_gbl_fixed_event_info
333 				    [ACPI_EVENT_POWER_BUTTON].
334 				    enable_register_id, ACPI_ENABLE_EVENT);
335 
336 	(void)
337 	    acpi_write_bit_register(acpi_gbl_fixed_event_info
338 				    [ACPI_EVENT_POWER_BUTTON].
339 				    status_register_id, ACPI_CLEAR_STATUS);
340 
341 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
342 	return_ACPI_STATUS(status);
343 }
344 
345 #endif				/* !ACPI_REDUCED_HARDWARE */
346