xref: /openbmc/linux/drivers/acpi/acpica/hwsleep.c (revision 95e9fd10)
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 - 2012, 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 #include <linux/module.h>
49 
50 #define _COMPONENT          ACPI_HARDWARE
51 ACPI_MODULE_NAME("hwsleep")
52 
53 #if (!ACPI_REDUCED_HARDWARE)	/* Entire module */
54 /*******************************************************************************
55  *
56  * FUNCTION:    acpi_hw_legacy_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 legacy FADT PM registers
63  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
64  *
65  ******************************************************************************/
66 acpi_status acpi_hw_legacy_sleep(u8 sleep_state)
67 {
68 	struct acpi_bit_register_info *sleep_type_reg_info;
69 	struct acpi_bit_register_info *sleep_enable_reg_info;
70 	u32 pm1a_control;
71 	u32 pm1b_control;
72 	u32 in_value;
73 	acpi_status status;
74 
75 	ACPI_FUNCTION_TRACE(hw_legacy_sleep);
76 
77 	sleep_type_reg_info =
78 	    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
79 	sleep_enable_reg_info =
80 	    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
81 
82 	/* Clear wake status */
83 
84 	status =
85 	    acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, ACPI_CLEAR_STATUS);
86 	if (ACPI_FAILURE(status)) {
87 		return_ACPI_STATUS(status);
88 	}
89 
90 	/* Clear all fixed and general purpose status bits */
91 
92 	status = acpi_hw_clear_acpi_status();
93 	if (ACPI_FAILURE(status)) {
94 		return_ACPI_STATUS(status);
95 	}
96 
97 	/*
98 	 * 1) Disable/Clear all GPEs
99 	 * 2) Enable all wakeup GPEs
100 	 */
101 	status = acpi_hw_disable_all_gpes();
102 	if (ACPI_FAILURE(status)) {
103 		return_ACPI_STATUS(status);
104 	}
105 	acpi_gbl_system_awake_and_running = FALSE;
106 
107 	status = acpi_hw_enable_all_wakeup_gpes();
108 	if (ACPI_FAILURE(status)) {
109 		return_ACPI_STATUS(status);
110 	}
111 
112 	/* Get current value of PM1A control */
113 
114 	status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
115 				       &pm1a_control);
116 	if (ACPI_FAILURE(status)) {
117 		return_ACPI_STATUS(status);
118 	}
119 	ACPI_DEBUG_PRINT((ACPI_DB_INIT,
120 			  "Entering sleep state [S%u]\n", sleep_state));
121 
122 	/* Clear the SLP_EN and SLP_TYP fields */
123 
124 	pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
125 			  sleep_enable_reg_info->access_bit_mask);
126 	pm1b_control = pm1a_control;
127 
128 	/* Insert the SLP_TYP bits */
129 
130 	pm1a_control |=
131 	    (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
132 	pm1b_control |=
133 	    (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
134 
135 	/*
136 	 * We split the writes of SLP_TYP and SLP_EN to workaround
137 	 * poorly implemented hardware.
138 	 */
139 
140 	/* Write #1: write the SLP_TYP data to the PM1 Control registers */
141 
142 	status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
143 	if (ACPI_FAILURE(status)) {
144 		return_ACPI_STATUS(status);
145 	}
146 
147 	/* Insert the sleep enable (SLP_EN) bit */
148 
149 	pm1a_control |= sleep_enable_reg_info->access_bit_mask;
150 	pm1b_control |= sleep_enable_reg_info->access_bit_mask;
151 
152 	/* Flush caches, as per ACPI specification */
153 
154 	ACPI_FLUSH_CPU_CACHE();
155 
156 	status = acpi_os_prepare_sleep(sleep_state, pm1a_control,
157 				       pm1b_control);
158 	if (ACPI_SKIP(status))
159 		return_ACPI_STATUS(AE_OK);
160 	if (ACPI_FAILURE(status))
161 		return_ACPI_STATUS(status);
162 	/* Write #2: Write both SLP_TYP + SLP_EN */
163 
164 	status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
165 	if (ACPI_FAILURE(status)) {
166 		return_ACPI_STATUS(status);
167 	}
168 
169 	if (sleep_state > ACPI_STATE_S3) {
170 		/*
171 		 * We wanted to sleep > S3, but it didn't happen (by virtue of the
172 		 * fact that we are still executing!)
173 		 *
174 		 * Wait ten seconds, then try again. This is to get S4/S5 to work on
175 		 * all machines.
176 		 *
177 		 * We wait so long to allow chipsets that poll this reg very slowly
178 		 * to still read the right value. Ideally, this block would go
179 		 * away entirely.
180 		 */
181 		acpi_os_stall(10000000);
182 
183 		status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
184 						sleep_enable_reg_info->
185 						access_bit_mask);
186 		if (ACPI_FAILURE(status)) {
187 			return_ACPI_STATUS(status);
188 		}
189 	}
190 
191 	/* Wait for transition back to Working State */
192 
193 	do {
194 		status =
195 		    acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
196 		if (ACPI_FAILURE(status)) {
197 			return_ACPI_STATUS(status);
198 		}
199 
200 	} while (!in_value);
201 
202 	return_ACPI_STATUS(AE_OK);
203 }
204 
205 /*******************************************************************************
206  *
207  * FUNCTION:    acpi_hw_legacy_wake_prep
208  *
209  * PARAMETERS:  sleep_state         - Which sleep state we just exited
210  *
211  * RETURN:      Status
212  *
213  * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
214  *              sleep.
215  *              Called with interrupts ENABLED.
216  *
217  ******************************************************************************/
218 
219 acpi_status acpi_hw_legacy_wake_prep(u8 sleep_state)
220 {
221 	acpi_status status;
222 	struct acpi_bit_register_info *sleep_type_reg_info;
223 	struct acpi_bit_register_info *sleep_enable_reg_info;
224 	u32 pm1a_control;
225 	u32 pm1b_control;
226 
227 	ACPI_FUNCTION_TRACE(hw_legacy_wake_prep);
228 
229 	/*
230 	 * Set SLP_TYPE and SLP_EN to state S0.
231 	 * This is unclear from the ACPI Spec, but it is required
232 	 * by some machines.
233 	 */
234 	status = acpi_get_sleep_type_data(ACPI_STATE_S0,
235 					  &acpi_gbl_sleep_type_a,
236 					  &acpi_gbl_sleep_type_b);
237 	if (ACPI_SUCCESS(status)) {
238 		sleep_type_reg_info =
239 		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
240 		sleep_enable_reg_info =
241 		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
242 
243 		/* Get current value of PM1A control */
244 
245 		status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
246 					       &pm1a_control);
247 		if (ACPI_SUCCESS(status)) {
248 
249 			/* Clear the SLP_EN and SLP_TYP fields */
250 
251 			pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
252 					  sleep_enable_reg_info->
253 					  access_bit_mask);
254 			pm1b_control = pm1a_control;
255 
256 			/* Insert the SLP_TYP bits */
257 
258 			pm1a_control |= (acpi_gbl_sleep_type_a <<
259 					 sleep_type_reg_info->bit_position);
260 			pm1b_control |= (acpi_gbl_sleep_type_b <<
261 					 sleep_type_reg_info->bit_position);
262 
263 			/* Write the control registers and ignore any errors */
264 
265 			(void)acpi_hw_write_pm1_control(pm1a_control,
266 							pm1b_control);
267 		}
268 	}
269 
270 	return_ACPI_STATUS(status);
271 }
272 
273 /*******************************************************************************
274  *
275  * FUNCTION:    acpi_hw_legacy_wake
276  *
277  * PARAMETERS:  sleep_state         - Which sleep state we just exited
278  *
279  * RETURN:      Status
280  *
281  * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
282  *              Called with interrupts ENABLED.
283  *
284  ******************************************************************************/
285 
286 acpi_status acpi_hw_legacy_wake(u8 sleep_state)
287 {
288 	acpi_status status;
289 
290 	ACPI_FUNCTION_TRACE(hw_legacy_wake);
291 
292 	/* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
293 
294 	acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
295 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);
296 
297 	/*
298 	 * GPEs must be enabled before _WAK is called as GPEs
299 	 * might get fired there
300 	 *
301 	 * Restore the GPEs:
302 	 * 1) Disable/Clear all GPEs
303 	 * 2) Enable all runtime GPEs
304 	 */
305 	status = acpi_hw_disable_all_gpes();
306 	if (ACPI_FAILURE(status)) {
307 		return_ACPI_STATUS(status);
308 	}
309 
310 	status = acpi_hw_enable_all_runtime_gpes();
311 	if (ACPI_FAILURE(status)) {
312 		return_ACPI_STATUS(status);
313 	}
314 
315 	/*
316 	 * Now we can execute _WAK, etc. Some machines require that the GPEs
317 	 * are enabled before the wake methods are executed.
318 	 */
319 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state);
320 
321 	/*
322 	 * Some BIOS code assumes that WAK_STS will be cleared on resume
323 	 * and use it to determine whether the system is rebooting or
324 	 * resuming. Clear WAK_STS for compatibility.
325 	 */
326 	acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, 1);
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