xref: /openbmc/linux/drivers/acpi/acpica/hwsleep.c (revision ce932d0c5589e9766e089c22c66890dfc48fbd94)
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  ******************************************************************************/
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 	if (sleep_state != ACPI_STATE_S5) {
99 		/*
100 		 * Disable BM arbitration. This feature is contained within an
101 		 * optional register (PM2 Control), so ignore a BAD_ADDRESS
102 		 * exception.
103 		 */
104 		status = acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1);
105 		if (ACPI_FAILURE(status) && (status != AE_BAD_ADDRESS)) {
106 			return_ACPI_STATUS(status);
107 		}
108 	}
109 
110 	/*
111 	 * 1) Disable/Clear all GPEs
112 	 * 2) Enable all wakeup GPEs
113 	 */
114 	status = acpi_hw_disable_all_gpes();
115 	if (ACPI_FAILURE(status)) {
116 		return_ACPI_STATUS(status);
117 	}
118 	acpi_gbl_system_awake_and_running = FALSE;
119 
120 	status = acpi_hw_enable_all_wakeup_gpes();
121 	if (ACPI_FAILURE(status)) {
122 		return_ACPI_STATUS(status);
123 	}
124 
125 	/* Optionally execute _GTS (Going To Sleep) */
126 
127 	if (flags & ACPI_EXECUTE_GTS) {
128 		acpi_hw_execute_sleep_method(METHOD_PATHNAME__GTS, sleep_state);
129 	}
130 
131 	/* Get current value of PM1A control */
132 
133 	status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
134 				       &pm1a_control);
135 	if (ACPI_FAILURE(status)) {
136 		return_ACPI_STATUS(status);
137 	}
138 	ACPI_DEBUG_PRINT((ACPI_DB_INIT,
139 			  "Entering sleep state [S%u]\n", sleep_state));
140 
141 	/* Clear the SLP_EN and SLP_TYP fields */
142 
143 	pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
144 			  sleep_enable_reg_info->access_bit_mask);
145 	pm1b_control = pm1a_control;
146 
147 	/* Insert the SLP_TYP bits */
148 
149 	pm1a_control |=
150 	    (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
151 	pm1b_control |=
152 	    (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
153 
154 	/*
155 	 * We split the writes of SLP_TYP and SLP_EN to workaround
156 	 * poorly implemented hardware.
157 	 */
158 
159 	/* Write #1: write the SLP_TYP data to the PM1 Control registers */
160 
161 	status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
162 	if (ACPI_FAILURE(status)) {
163 		return_ACPI_STATUS(status);
164 	}
165 
166 	/* Insert the sleep enable (SLP_EN) bit */
167 
168 	pm1a_control |= sleep_enable_reg_info->access_bit_mask;
169 	pm1b_control |= sleep_enable_reg_info->access_bit_mask;
170 
171 	/* Flush caches, as per ACPI specification */
172 
173 	ACPI_FLUSH_CPU_CACHE();
174 
175 	status = acpi_os_prepare_sleep(sleep_state, pm1a_control,
176 				       pm1b_control);
177 	if (ACPI_SKIP(status))
178 		return_ACPI_STATUS(AE_OK);
179 	if (ACPI_FAILURE(status))
180 		return_ACPI_STATUS(status);
181 	/* Write #2: Write both SLP_TYP + SLP_EN */
182 
183 	status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
184 	if (ACPI_FAILURE(status)) {
185 		return_ACPI_STATUS(status);
186 	}
187 
188 	if (sleep_state > ACPI_STATE_S3) {
189 		/*
190 		 * We wanted to sleep > S3, but it didn't happen (by virtue of the
191 		 * fact that we are still executing!)
192 		 *
193 		 * Wait ten seconds, then try again. This is to get S4/S5 to work on
194 		 * all machines.
195 		 *
196 		 * We wait so long to allow chipsets that poll this reg very slowly
197 		 * to still read the right value. Ideally, this block would go
198 		 * away entirely.
199 		 */
200 		acpi_os_stall(10000000);
201 
202 		status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
203 						sleep_enable_reg_info->
204 						access_bit_mask);
205 		if (ACPI_FAILURE(status)) {
206 			return_ACPI_STATUS(status);
207 		}
208 	}
209 
210 	/* Wait for transition back to Working State */
211 
212 	do {
213 		status =
214 		    acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
215 		if (ACPI_FAILURE(status)) {
216 			return_ACPI_STATUS(status);
217 		}
218 
219 	} while (!in_value);
220 
221 	return_ACPI_STATUS(AE_OK);
222 }
223 
224 /*******************************************************************************
225  *
226  * FUNCTION:    acpi_hw_legacy_wake_prep
227  *
228  * PARAMETERS:  sleep_state         - Which sleep state we just exited
229  *              Flags               - ACPI_EXECUTE_BFS to run optional method
230  *
231  * RETURN:      Status
232  *
233  * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
234  *              sleep.
235  *              Called with interrupts ENABLED.
236  *
237  ******************************************************************************/
238 
239 acpi_status acpi_hw_legacy_wake_prep(u8 sleep_state, u8 flags)
240 {
241 	acpi_status status;
242 	struct acpi_bit_register_info *sleep_type_reg_info;
243 	struct acpi_bit_register_info *sleep_enable_reg_info;
244 	u32 pm1a_control;
245 	u32 pm1b_control;
246 
247 	ACPI_FUNCTION_TRACE(hw_legacy_wake_prep);
248 
249 	/*
250 	 * Set SLP_TYPE and SLP_EN to state S0.
251 	 * This is unclear from the ACPI Spec, but it is required
252 	 * by some machines.
253 	 */
254 	status = acpi_get_sleep_type_data(ACPI_STATE_S0,
255 					  &acpi_gbl_sleep_type_a,
256 					  &acpi_gbl_sleep_type_b);
257 	if (ACPI_SUCCESS(status)) {
258 		sleep_type_reg_info =
259 		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
260 		sleep_enable_reg_info =
261 		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
262 
263 		/* Get current value of PM1A control */
264 
265 		status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
266 					       &pm1a_control);
267 		if (ACPI_SUCCESS(status)) {
268 
269 			/* Clear the SLP_EN and SLP_TYP fields */
270 
271 			pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
272 					  sleep_enable_reg_info->
273 					  access_bit_mask);
274 			pm1b_control = pm1a_control;
275 
276 			/* Insert the SLP_TYP bits */
277 
278 			pm1a_control |= (acpi_gbl_sleep_type_a <<
279 					 sleep_type_reg_info->bit_position);
280 			pm1b_control |= (acpi_gbl_sleep_type_b <<
281 					 sleep_type_reg_info->bit_position);
282 
283 			/* Write the control registers and ignore any errors */
284 
285 			(void)acpi_hw_write_pm1_control(pm1a_control,
286 							pm1b_control);
287 		}
288 	}
289 
290 	/* Optionally execute _BFS (Back From Sleep) */
291 
292 	if (flags & ACPI_EXECUTE_BFS) {
293 		acpi_hw_execute_sleep_method(METHOD_PATHNAME__BFS, sleep_state);
294 	}
295 	return_ACPI_STATUS(status);
296 }
297 
298 /*******************************************************************************
299  *
300  * FUNCTION:    acpi_hw_legacy_wake
301  *
302  * PARAMETERS:  sleep_state         - Which sleep state we just exited
303  *              Flags               - Reserved, set to zero
304  *
305  * RETURN:      Status
306  *
307  * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
308  *              Called with interrupts ENABLED.
309  *
310  ******************************************************************************/
311 
312 acpi_status acpi_hw_legacy_wake(u8 sleep_state, u8 flags)
313 {
314 	acpi_status status;
315 
316 	ACPI_FUNCTION_TRACE(hw_legacy_wake);
317 
318 	/* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
319 
320 	acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
321 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);
322 
323 	/*
324 	 * GPEs must be enabled before _WAK is called as GPEs
325 	 * might get fired there
326 	 *
327 	 * Restore the GPEs:
328 	 * 1) Disable/Clear all GPEs
329 	 * 2) Enable all runtime GPEs
330 	 */
331 	status = acpi_hw_disable_all_gpes();
332 	if (ACPI_FAILURE(status)) {
333 		return_ACPI_STATUS(status);
334 	}
335 
336 	status = acpi_hw_enable_all_runtime_gpes();
337 	if (ACPI_FAILURE(status)) {
338 		return_ACPI_STATUS(status);
339 	}
340 
341 	/*
342 	 * Now we can execute _WAK, etc. Some machines require that the GPEs
343 	 * are enabled before the wake methods are executed.
344 	 */
345 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state);
346 
347 	/*
348 	 * Some BIOS code assumes that WAK_STS will be cleared on resume
349 	 * and use it to determine whether the system is rebooting or
350 	 * resuming. Clear WAK_STS for compatibility.
351 	 */
352 	acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, 1);
353 	acpi_gbl_system_awake_and_running = TRUE;
354 
355 	/* Enable power button */
356 
357 	(void)
358 	    acpi_write_bit_register(acpi_gbl_fixed_event_info
359 				    [ACPI_EVENT_POWER_BUTTON].
360 				    enable_register_id, ACPI_ENABLE_EVENT);
361 
362 	(void)
363 	    acpi_write_bit_register(acpi_gbl_fixed_event_info
364 				    [ACPI_EVENT_POWER_BUTTON].
365 				    status_register_id, ACPI_CLEAR_STATUS);
366 
367 	/*
368 	 * Enable BM arbitration. This feature is contained within an
369 	 * optional register (PM2 Control), so ignore a BAD_ADDRESS
370 	 * exception.
371 	 */
372 	status = acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0);
373 	if (ACPI_FAILURE(status) && (status != AE_BAD_ADDRESS)) {
374 		return_ACPI_STATUS(status);
375 	}
376 
377 	acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
378 	return_ACPI_STATUS(status);
379 }
380 
381 #endif				/* !ACPI_REDUCED_HARDWARE */
382