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  *              Flags               - ACPI_EXECUTE_GTS to run optional method
60  *
61  * RETURN:      Status
62  *
63  * DESCRIPTION: Enter a system sleep state via the legacy FADT PM registers
64  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
65  *
66  ******************************************************************************/
acpi_hw_legacy_sleep(u8 sleep_state,u8 flags)67 acpi_status acpi_hw_legacy_sleep(u8 sleep_state, u8 flags)
68 {
69 	struct acpi_bit_register_info *sleep_type_reg_info;
70 	struct acpi_bit_register_info *sleep_enable_reg_info;
71 	u32 pm1a_control;
72 	u32 pm1b_control;
73 	u32 in_value;
74 	acpi_status status;
75 
76 	ACPI_FUNCTION_TRACE(hw_legacy_sleep);
77 
78 	sleep_type_reg_info =
79 	    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
80 	sleep_enable_reg_info =
81 	    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
82 
83 	/* Clear wake status */
84 
85 	status =
86 	    acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, ACPI_CLEAR_STATUS);
87 	if (ACPI_FAILURE(status)) {
88 		return_ACPI_STATUS(status);
89 	}
90 
91 	/* Clear all fixed and general purpose status bits */
92 
93 	status = acpi_hw_clear_acpi_status();
94 	if (ACPI_FAILURE(status)) {
95 		return_ACPI_STATUS(status);
96 	}
97 
98 	/*
99 	 * 1) Disable/Clear all GPEs
100 	 * 2) Enable all wakeup GPEs
101 	 */
102 	status = acpi_hw_disable_all_gpes();
103 	if (ACPI_FAILURE(status)) {
104 		return_ACPI_STATUS(status);
105 	}
106 	acpi_gbl_system_awake_and_running = FALSE;
107 
108 	status = acpi_hw_enable_all_wakeup_gpes();
109 	if (ACPI_FAILURE(status)) {
110 		return_ACPI_STATUS(status);
111 	}
112 
113 	/* Optionally execute _GTS (Going To Sleep) */
114 
115 	if (flags & ACPI_EXECUTE_GTS) {
116 		acpi_hw_execute_sleep_method(METHOD_PATHNAME__GTS, sleep_state);
117 	}
118 
119 	/* Get current value of PM1A control */
120 
121 	status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
122 				       &pm1a_control);
123 	if (ACPI_FAILURE(status)) {
124 		return_ACPI_STATUS(status);
125 	}
126 	ACPI_DEBUG_PRINT((ACPI_DB_INIT,
127 			  "Entering sleep state [S%u]\n", sleep_state));
128 
129 	/* Clear the SLP_EN and SLP_TYP fields */
130 
131 	pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
132 			  sleep_enable_reg_info->access_bit_mask);
133 	pm1b_control = pm1a_control;
134 
135 	/* Insert the SLP_TYP bits */
136 
137 	pm1a_control |=
138 	    (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
139 	pm1b_control |=
140 	    (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
141 
142 	/*
143 	 * We split the writes of SLP_TYP and SLP_EN to workaround
144 	 * poorly implemented hardware.
145 	 */
146 
147 	/* Write #1: write the SLP_TYP data to the PM1 Control registers */
148 
149 	status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
150 	if (ACPI_FAILURE(status)) {
151 		return_ACPI_STATUS(status);
152 	}
153 
154 	/* Insert the sleep enable (SLP_EN) bit */
155 
156 	pm1a_control |= sleep_enable_reg_info->access_bit_mask;
157 	pm1b_control |= sleep_enable_reg_info->access_bit_mask;
158 
159 	/* Flush caches, as per ACPI specification */
160 
161 	ACPI_FLUSH_CPU_CACHE();
162 
163 	status = acpi_os_prepare_sleep(sleep_state, pm1a_control,
164 				       pm1b_control);
165 	if (ACPI_SKIP(status))
166 		return_ACPI_STATUS(AE_OK);
167 	if (ACPI_FAILURE(status))
168 		return_ACPI_STATUS(status);
169 	/* Write #2: Write both SLP_TYP + SLP_EN */
170 
171 	status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
172 	if (ACPI_FAILURE(status)) {
173 		return_ACPI_STATUS(status);
174 	}
175 
176 	if (sleep_state > ACPI_STATE_S3) {
177 		/*
178 		 * We wanted to sleep > S3, but it didn't happen (by virtue of the
179 		 * fact that we are still executing!)
180 		 *
181 		 * Wait ten seconds, then try again. This is to get S4/S5 to work on
182 		 * all machines.
183 		 *
184 		 * We wait so long to allow chipsets that poll this reg very slowly
185 		 * to still read the right value. Ideally, this block would go
186 		 * away entirely.
187 		 */
188 		acpi_os_stall(10000000);
189 
190 		status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
191 						sleep_enable_reg_info->
192 						access_bit_mask);
193 		if (ACPI_FAILURE(status)) {
194 			return_ACPI_STATUS(status);
195 		}
196 	}
197 
198 	/* Wait for transition back to Working State */
199 
200 	do {
201 		status =
202 		    acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
203 		if (ACPI_FAILURE(status)) {
204 			return_ACPI_STATUS(status);
205 		}
206 
207 	} while (!in_value);
208 
209 	return_ACPI_STATUS(AE_OK);
210 }
211 
212 /*******************************************************************************
213  *
214  * FUNCTION:    acpi_hw_legacy_wake_prep
215  *
216  * PARAMETERS:  sleep_state         - Which sleep state we just exited
217  *              Flags               - ACPI_EXECUTE_BFS to run optional method
218  *
219  * RETURN:      Status
220  *
221  * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
222  *              sleep.
223  *              Called with interrupts ENABLED.
224  *
225  ******************************************************************************/
226 
acpi_hw_legacy_wake_prep(u8 sleep_state,u8 flags)227 acpi_status acpi_hw_legacy_wake_prep(u8 sleep_state, u8 flags)
228 {
229 	acpi_status status;
230 	struct acpi_bit_register_info *sleep_type_reg_info;
231 	struct acpi_bit_register_info *sleep_enable_reg_info;
232 	u32 pm1a_control;
233 	u32 pm1b_control;
234 
235 	ACPI_FUNCTION_TRACE(hw_legacy_wake_prep);
236 
237 	/*
238 	 * Set SLP_TYPE and SLP_EN to state S0.
239 	 * This is unclear from the ACPI Spec, but it is required
240 	 * by some machines.
241 	 */
242 	status = acpi_get_sleep_type_data(ACPI_STATE_S0,
243 					  &acpi_gbl_sleep_type_a,
244 					  &acpi_gbl_sleep_type_b);
245 	if (ACPI_SUCCESS(status)) {
246 		sleep_type_reg_info =
247 		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
248 		sleep_enable_reg_info =
249 		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
250 
251 		/* Get current value of PM1A control */
252 
253 		status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
254 					       &pm1a_control);
255 		if (ACPI_SUCCESS(status)) {
256 
257 			/* Clear the SLP_EN and SLP_TYP fields */
258 
259 			pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
260 					  sleep_enable_reg_info->
261 					  access_bit_mask);
262 			pm1b_control = pm1a_control;
263 
264 			/* Insert the SLP_TYP bits */
265 
266 			pm1a_control |= (acpi_gbl_sleep_type_a <<
267 					 sleep_type_reg_info->bit_position);
268 			pm1b_control |= (acpi_gbl_sleep_type_b <<
269 					 sleep_type_reg_info->bit_position);
270 
271 			/* Write the control registers and ignore any errors */
272 
273 			(void)acpi_hw_write_pm1_control(pm1a_control,
274 							pm1b_control);
275 		}
276 	}
277 
278 	/* Optionally execute _BFS (Back From Sleep) */
279 
280 	if (flags & ACPI_EXECUTE_BFS) {
281 		acpi_hw_execute_sleep_method(METHOD_PATHNAME__BFS, sleep_state);
282 	}
283 	return_ACPI_STATUS(status);
284 }
285 
286 /*******************************************************************************
287  *
288  * FUNCTION:    acpi_hw_legacy_wake
289  *
290  * PARAMETERS:  sleep_state         - Which sleep state we just exited
291  *              Flags               - Reserved, set to zero
292  *
293  * RETURN:      Status
294  *
295  * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
296  *              Called with interrupts ENABLED.
297  *
298  ******************************************************************************/
299 
acpi_hw_legacy_wake(u8 sleep_state,u8 flags)300 acpi_status acpi_hw_legacy_wake(u8 sleep_state, u8 flags)
301 {
302 	acpi_status status;
303 
304 	ACPI_FUNCTION_TRACE(hw_legacy_wake);
305 
306 	/* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
307 
308 	acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
309 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);
310 
311 	/*
312 	 * GPEs must be enabled before _WAK is called as GPEs
313 	 * might get fired there
314 	 *
315 	 * Restore the GPEs:
316 	 * 1) Disable/Clear all GPEs
317 	 * 2) Enable all runtime GPEs
318 	 */
319 	status = acpi_hw_disable_all_gpes();
320 	if (ACPI_FAILURE(status)) {
321 		return_ACPI_STATUS(status);
322 	}
323 
324 	status = acpi_hw_enable_all_runtime_gpes();
325 	if (ACPI_FAILURE(status)) {
326 		return_ACPI_STATUS(status);
327 	}
328 
329 	/*
330 	 * Now we can execute _WAK, etc. Some machines require that the GPEs
331 	 * are enabled before the wake methods are executed.
332 	 */
333 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state);
334 
335 	/*
336 	 * Some BIOS code assumes that WAK_STS will be cleared on resume
337 	 * and use it to determine whether the system is rebooting or
338 	 * resuming. Clear WAK_STS for compatibility.
339 	 */
340 	acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, 1);
341 	acpi_gbl_system_awake_and_running = TRUE;
342 
343 	/* Enable power button */
344 
345 	(void)
346 	    acpi_write_bit_register(acpi_gbl_fixed_event_info
347 				    [ACPI_EVENT_POWER_BUTTON].
348 				    enable_register_id, ACPI_ENABLE_EVENT);
349 
350 	(void)
351 	    acpi_write_bit_register(acpi_gbl_fixed_event_info
352 				    [ACPI_EVENT_POWER_BUTTON].
353 				    status_register_id, ACPI_CLEAR_STATUS);
354 
355 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
356 	return_ACPI_STATUS(status);
357 }
358 
359 #endif				/* !ACPI_REDUCED_HARDWARE */
360