hwsleep.c 18 KB

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  1. /******************************************************************************
  2. *
  3. * Name: hwsleep.c - ACPI Hardware Sleep/Wake Interface
  4. *
  5. *****************************************************************************/
  6. /*
  7. * Copyright (C) 2000 - 2008, Intel Corp.
  8. * All rights reserved.
  9. *
  10. * Redistribution and use in source and binary forms, with or without
  11. * modification, are permitted provided that the following conditions
  12. * are met:
  13. * 1. Redistributions of source code must retain the above copyright
  14. * notice, this list of conditions, and the following disclaimer,
  15. * without modification.
  16. * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  17. * substantially similar to the "NO WARRANTY" disclaimer below
  18. * ("Disclaimer") and any redistribution must be conditioned upon
  19. * including a substantially similar Disclaimer requirement for further
  20. * binary redistribution.
  21. * 3. Neither the names of the above-listed copyright holders nor the names
  22. * of any contributors may be used to endorse or promote products derived
  23. * from this software without specific prior written permission.
  24. *
  25. * Alternatively, this software may be distributed under the terms of the
  26. * GNU General Public License ("GPL") version 2 as published by the Free
  27. * Software Foundation.
  28. *
  29. * NO WARRANTY
  30. * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  31. * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  32. * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  33. * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  34. * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  35. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  36. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  37. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  38. * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  39. * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  40. * POSSIBILITY OF SUCH DAMAGES.
  41. */
  42. #include <acpi/acpi.h>
  43. #include "accommon.h"
  44. #include "actables.h"
  45. #define _COMPONENT ACPI_HARDWARE
  46. ACPI_MODULE_NAME("hwsleep")
  47. /*******************************************************************************
  48. *
  49. * FUNCTION: acpi_set_firmware_waking_vector
  50. *
  51. * PARAMETERS: physical_address - 32-bit physical address of ACPI real mode
  52. * entry point.
  53. *
  54. * RETURN: Status
  55. *
  56. * DESCRIPTION: Sets the 32-bit firmware_waking_vector field of the FACS
  57. *
  58. ******************************************************************************/
  59. acpi_status
  60. acpi_set_firmware_waking_vector(u32 physical_address)
  61. {
  62. ACPI_FUNCTION_TRACE(acpi_set_firmware_waking_vector);
  63. /*
  64. * According to the ACPI specification 2.0c and later, the 64-bit
  65. * waking vector should be cleared and the 32-bit waking vector should
  66. * be used, unless we want the wake-up code to be called by the BIOS in
  67. * Protected Mode. Some systems (for example HP dv5-1004nr) are known
  68. * to fail to resume if the 64-bit vector is used.
  69. */
  70. /* Set the 32-bit vector */
  71. acpi_gbl_FACS->firmware_waking_vector = physical_address;
  72. /* Clear the 64-bit vector if it exists */
  73. if ((acpi_gbl_FACS->length > 32) && (acpi_gbl_FACS->version >= 1)) {
  74. acpi_gbl_FACS->xfirmware_waking_vector = 0;
  75. }
  76. return_ACPI_STATUS(AE_OK);
  77. }
  78. ACPI_EXPORT_SYMBOL(acpi_set_firmware_waking_vector)
  79. #if ACPI_MACHINE_WIDTH == 64
  80. /*******************************************************************************
  81. *
  82. * FUNCTION: acpi_set_firmware_waking_vector64
  83. *
  84. * PARAMETERS: physical_address - 64-bit physical address of ACPI protected
  85. * mode entry point.
  86. *
  87. * RETURN: Status
  88. *
  89. * DESCRIPTION: Sets the 64-bit X_firmware_waking_vector field of the FACS, if
  90. * it exists in the table. This function is intended for use with
  91. * 64-bit host operating systems.
  92. *
  93. ******************************************************************************/
  94. acpi_status
  95. acpi_set_firmware_waking_vector64(u64 physical_address)
  96. {
  97. ACPI_FUNCTION_TRACE(acpi_set_firmware_waking_vector64);
  98. /* Determine if the 64-bit vector actually exists */
  99. if ((acpi_gbl_FACS->length <= 32) || (acpi_gbl_FACS->version < 1)) {
  100. return_ACPI_STATUS(AE_NOT_EXIST);
  101. }
  102. /* Clear 32-bit vector, set the 64-bit X_ vector */
  103. acpi_gbl_FACS->firmware_waking_vector = 0;
  104. acpi_gbl_FACS->xfirmware_waking_vector = physical_address;
  105. return_ACPI_STATUS(AE_OK);
  106. }
  107. ACPI_EXPORT_SYMBOL(acpi_set_firmware_waking_vector64)
  108. #endif
  109. /*******************************************************************************
  110. *
  111. * FUNCTION: acpi_enter_sleep_state_prep
  112. *
  113. * PARAMETERS: sleep_state - Which sleep state to enter
  114. *
  115. * RETURN: Status
  116. *
  117. * DESCRIPTION: Prepare to enter a system sleep state (see ACPI 2.0 spec p 231)
  118. * This function must execute with interrupts enabled.
  119. * We break sleeping into 2 stages so that OSPM can handle
  120. * various OS-specific tasks between the two steps.
  121. *
  122. ******************************************************************************/
  123. acpi_status acpi_enter_sleep_state_prep(u8 sleep_state)
  124. {
  125. acpi_status status;
  126. struct acpi_object_list arg_list;
  127. union acpi_object arg;
  128. ACPI_FUNCTION_TRACE(acpi_enter_sleep_state_prep);
  129. /* _PSW methods could be run here to enable wake-on keyboard, LAN, etc. */
  130. status = acpi_get_sleep_type_data(sleep_state,
  131. &acpi_gbl_sleep_type_a,
  132. &acpi_gbl_sleep_type_b);
  133. if (ACPI_FAILURE(status)) {
  134. return_ACPI_STATUS(status);
  135. }
  136. /* Setup parameter object */
  137. arg_list.count = 1;
  138. arg_list.pointer = &arg;
  139. arg.type = ACPI_TYPE_INTEGER;
  140. arg.integer.value = sleep_state;
  141. /* Run the _PTS method */
  142. status = acpi_evaluate_object(NULL, METHOD_NAME__PTS, &arg_list, NULL);
  143. if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  144. return_ACPI_STATUS(status);
  145. }
  146. /* Setup the argument to _SST */
  147. switch (sleep_state) {
  148. case ACPI_STATE_S0:
  149. arg.integer.value = ACPI_SST_WORKING;
  150. break;
  151. case ACPI_STATE_S1:
  152. case ACPI_STATE_S2:
  153. case ACPI_STATE_S3:
  154. arg.integer.value = ACPI_SST_SLEEPING;
  155. break;
  156. case ACPI_STATE_S4:
  157. arg.integer.value = ACPI_SST_SLEEP_CONTEXT;
  158. break;
  159. default:
  160. arg.integer.value = ACPI_SST_INDICATOR_OFF; /* Default is off */
  161. break;
  162. }
  163. /*
  164. * Set the system indicators to show the desired sleep state.
  165. * _SST is an optional method (return no error if not found)
  166. */
  167. status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
  168. if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  169. ACPI_EXCEPTION((AE_INFO, status,
  170. "While executing method _SST"));
  171. }
  172. return_ACPI_STATUS(AE_OK);
  173. }
  174. ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state_prep)
  175. static unsigned int gts, bfs;
  176. module_param(gts, uint, 0644);
  177. module_param(bfs, uint, 0644);
  178. MODULE_PARM_DESC(gts, "Enable evaluation of _GTS on suspend.");
  179. MODULE_PARM_DESC(bfs, "Enable evaluation of _BFS on resume".);
  180. /*******************************************************************************
  181. *
  182. * FUNCTION: acpi_enter_sleep_state
  183. *
  184. * PARAMETERS: sleep_state - Which sleep state to enter
  185. *
  186. * RETURN: Status
  187. *
  188. * DESCRIPTION: Enter a system sleep state (see ACPI 2.0 spec p 231)
  189. * THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
  190. *
  191. ******************************************************************************/
  192. acpi_status asmlinkage acpi_enter_sleep_state(u8 sleep_state)
  193. {
  194. u32 pm1a_control;
  195. u32 pm1b_control;
  196. struct acpi_bit_register_info *sleep_type_reg_info;
  197. struct acpi_bit_register_info *sleep_enable_reg_info;
  198. u32 in_value;
  199. struct acpi_object_list arg_list;
  200. union acpi_object arg;
  201. acpi_status status;
  202. ACPI_FUNCTION_TRACE(acpi_enter_sleep_state);
  203. if ((acpi_gbl_sleep_type_a > ACPI_SLEEP_TYPE_MAX) ||
  204. (acpi_gbl_sleep_type_b > ACPI_SLEEP_TYPE_MAX)) {
  205. ACPI_ERROR((AE_INFO, "Sleep values out of range: A=%X B=%X",
  206. acpi_gbl_sleep_type_a, acpi_gbl_sleep_type_b));
  207. return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
  208. }
  209. sleep_type_reg_info =
  210. acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
  211. sleep_enable_reg_info =
  212. acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
  213. /* Clear wake status */
  214. status =
  215. acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, ACPI_CLEAR_STATUS);
  216. if (ACPI_FAILURE(status)) {
  217. return_ACPI_STATUS(status);
  218. }
  219. /* Clear all fixed and general purpose status bits */
  220. status = acpi_hw_clear_acpi_status();
  221. if (ACPI_FAILURE(status)) {
  222. return_ACPI_STATUS(status);
  223. }
  224. /*
  225. * 1) Disable/Clear all GPEs
  226. * 2) Enable all wakeup GPEs
  227. */
  228. status = acpi_hw_disable_all_gpes();
  229. if (ACPI_FAILURE(status)) {
  230. return_ACPI_STATUS(status);
  231. }
  232. acpi_gbl_system_awake_and_running = FALSE;
  233. status = acpi_hw_enable_all_wakeup_gpes();
  234. if (ACPI_FAILURE(status)) {
  235. return_ACPI_STATUS(status);
  236. }
  237. if (gts) {
  238. /* Execute the _GTS method */
  239. arg_list.count = 1;
  240. arg_list.pointer = &arg;
  241. arg.type = ACPI_TYPE_INTEGER;
  242. arg.integer.value = sleep_state;
  243. status = acpi_evaluate_object(NULL, METHOD_NAME__GTS, &arg_list, NULL);
  244. if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  245. return_ACPI_STATUS(status);
  246. }
  247. }
  248. /* Get current value of PM1A control */
  249. status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
  250. &pm1a_control);
  251. if (ACPI_FAILURE(status)) {
  252. return_ACPI_STATUS(status);
  253. }
  254. ACPI_DEBUG_PRINT((ACPI_DB_INIT,
  255. "Entering sleep state [S%d]\n", sleep_state));
  256. /* Clear the SLP_EN and SLP_TYP fields */
  257. pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
  258. sleep_enable_reg_info->access_bit_mask);
  259. pm1b_control = pm1a_control;
  260. /* Insert the SLP_TYP bits */
  261. pm1a_control |=
  262. (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
  263. pm1b_control |=
  264. (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
  265. /*
  266. * We split the writes of SLP_TYP and SLP_EN to workaround
  267. * poorly implemented hardware.
  268. */
  269. /* Write #1: write the SLP_TYP data to the PM1 Control registers */
  270. status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
  271. if (ACPI_FAILURE(status)) {
  272. return_ACPI_STATUS(status);
  273. }
  274. /* Insert the sleep enable (SLP_EN) bit */
  275. pm1a_control |= sleep_enable_reg_info->access_bit_mask;
  276. pm1b_control |= sleep_enable_reg_info->access_bit_mask;
  277. /* Flush caches, as per ACPI specification */
  278. ACPI_FLUSH_CPU_CACHE();
  279. /* Write #2: Write both SLP_TYP + SLP_EN */
  280. status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
  281. if (ACPI_FAILURE(status)) {
  282. return_ACPI_STATUS(status);
  283. }
  284. if (sleep_state > ACPI_STATE_S3) {
  285. /*
  286. * We wanted to sleep > S3, but it didn't happen (by virtue of the
  287. * fact that we are still executing!)
  288. *
  289. * Wait ten seconds, then try again. This is to get S4/S5 to work on
  290. * all machines.
  291. *
  292. * We wait so long to allow chipsets that poll this reg very slowly
  293. * to still read the right value. Ideally, this block would go
  294. * away entirely.
  295. */
  296. acpi_os_stall(10000000);
  297. status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
  298. sleep_enable_reg_info->
  299. access_bit_mask);
  300. if (ACPI_FAILURE(status)) {
  301. return_ACPI_STATUS(status);
  302. }
  303. }
  304. /* Wait until we enter sleep state */
  305. do {
  306. status = acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS,
  307. &in_value);
  308. if (ACPI_FAILURE(status)) {
  309. return_ACPI_STATUS(status);
  310. }
  311. /* Spin until we wake */
  312. } while (!in_value);
  313. return_ACPI_STATUS(AE_OK);
  314. }
  315. ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state)
  316. /*******************************************************************************
  317. *
  318. * FUNCTION: acpi_enter_sleep_state_s4bios
  319. *
  320. * PARAMETERS: None
  321. *
  322. * RETURN: Status
  323. *
  324. * DESCRIPTION: Perform a S4 bios request.
  325. * THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
  326. *
  327. ******************************************************************************/
  328. acpi_status asmlinkage acpi_enter_sleep_state_s4bios(void)
  329. {
  330. u32 in_value;
  331. acpi_status status;
  332. ACPI_FUNCTION_TRACE(acpi_enter_sleep_state_s4bios);
  333. /* Clear the wake status bit (PM1) */
  334. status =
  335. acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, ACPI_CLEAR_STATUS);
  336. if (ACPI_FAILURE(status)) {
  337. return_ACPI_STATUS(status);
  338. }
  339. status = acpi_hw_clear_acpi_status();
  340. if (ACPI_FAILURE(status)) {
  341. return_ACPI_STATUS(status);
  342. }
  343. /*
  344. * 1) Disable/Clear all GPEs
  345. * 2) Enable all wakeup GPEs
  346. */
  347. status = acpi_hw_disable_all_gpes();
  348. if (ACPI_FAILURE(status)) {
  349. return_ACPI_STATUS(status);
  350. }
  351. acpi_gbl_system_awake_and_running = FALSE;
  352. status = acpi_hw_enable_all_wakeup_gpes();
  353. if (ACPI_FAILURE(status)) {
  354. return_ACPI_STATUS(status);
  355. }
  356. ACPI_FLUSH_CPU_CACHE();
  357. status = acpi_hw_write_port(acpi_gbl_FADT.smi_command,
  358. (u32) acpi_gbl_FADT.S4bios_request, 8);
  359. do {
  360. acpi_os_stall(1000);
  361. status =
  362. acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
  363. if (ACPI_FAILURE(status)) {
  364. return_ACPI_STATUS(status);
  365. }
  366. } while (!in_value);
  367. return_ACPI_STATUS(AE_OK);
  368. }
  369. ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state_s4bios)
  370. /*******************************************************************************
  371. *
  372. * FUNCTION: acpi_leave_sleep_state_prep
  373. *
  374. * PARAMETERS: sleep_state - Which sleep state we are exiting
  375. *
  376. * RETURN: Status
  377. *
  378. * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
  379. * sleep.
  380. * Called with interrupts DISABLED.
  381. *
  382. ******************************************************************************/
  383. acpi_status acpi_leave_sleep_state_prep(u8 sleep_state)
  384. {
  385. struct acpi_object_list arg_list;
  386. union acpi_object arg;
  387. acpi_status status;
  388. struct acpi_bit_register_info *sleep_type_reg_info;
  389. struct acpi_bit_register_info *sleep_enable_reg_info;
  390. u32 pm1a_control;
  391. u32 pm1b_control;
  392. ACPI_FUNCTION_TRACE(acpi_leave_sleep_state_prep);
  393. /*
  394. * Set SLP_TYPE and SLP_EN to state S0.
  395. * This is unclear from the ACPI Spec, but it is required
  396. * by some machines.
  397. */
  398. status = acpi_get_sleep_type_data(ACPI_STATE_S0,
  399. &acpi_gbl_sleep_type_a,
  400. &acpi_gbl_sleep_type_b);
  401. if (ACPI_SUCCESS(status)) {
  402. sleep_type_reg_info =
  403. acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
  404. sleep_enable_reg_info =
  405. acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
  406. /* Get current value of PM1A control */
  407. status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
  408. &pm1a_control);
  409. if (ACPI_SUCCESS(status)) {
  410. /* Clear the SLP_EN and SLP_TYP fields */
  411. pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
  412. sleep_enable_reg_info->
  413. access_bit_mask);
  414. pm1b_control = pm1a_control;
  415. /* Insert the SLP_TYP bits */
  416. pm1a_control |= (acpi_gbl_sleep_type_a <<
  417. sleep_type_reg_info->bit_position);
  418. pm1b_control |= (acpi_gbl_sleep_type_b <<
  419. sleep_type_reg_info->bit_position);
  420. /* Write the control registers and ignore any errors */
  421. (void)acpi_hw_write_pm1_control(pm1a_control,
  422. pm1b_control);
  423. }
  424. }
  425. if (bfs) {
  426. /* Execute the _BFS method */
  427. arg_list.count = 1;
  428. arg_list.pointer = &arg;
  429. arg.type = ACPI_TYPE_INTEGER;
  430. arg.integer.value = sleep_state;
  431. status = acpi_evaluate_object(NULL, METHOD_NAME__BFS, &arg_list, NULL);
  432. if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  433. ACPI_EXCEPTION((AE_INFO, status, "During Method _BFS"));
  434. }
  435. }
  436. return_ACPI_STATUS(status);
  437. }
  438. /*******************************************************************************
  439. *
  440. * FUNCTION: acpi_leave_sleep_state
  441. *
  442. * PARAMETERS: sleep_state - Which sleep state we just exited
  443. *
  444. * RETURN: Status
  445. *
  446. * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
  447. * Called with interrupts ENABLED.
  448. *
  449. ******************************************************************************/
  450. acpi_status acpi_leave_sleep_state(u8 sleep_state)
  451. {
  452. struct acpi_object_list arg_list;
  453. union acpi_object arg;
  454. acpi_status status;
  455. ACPI_FUNCTION_TRACE(acpi_leave_sleep_state);
  456. /* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
  457. acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
  458. /* Setup parameter object */
  459. arg_list.count = 1;
  460. arg_list.pointer = &arg;
  461. arg.type = ACPI_TYPE_INTEGER;
  462. /* Ignore any errors from these methods */
  463. arg.integer.value = ACPI_SST_WAKING;
  464. status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
  465. if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  466. ACPI_EXCEPTION((AE_INFO, status, "During Method _SST"));
  467. }
  468. /*
  469. * GPEs must be enabled before _WAK is called as GPEs
  470. * might get fired there
  471. *
  472. * Restore the GPEs:
  473. * 1) Disable/Clear all GPEs
  474. * 2) Enable all runtime GPEs
  475. */
  476. status = acpi_hw_disable_all_gpes();
  477. if (ACPI_FAILURE(status)) {
  478. return_ACPI_STATUS(status);
  479. }
  480. status = acpi_hw_enable_all_runtime_gpes();
  481. if (ACPI_FAILURE(status)) {
  482. return_ACPI_STATUS(status);
  483. }
  484. arg.integer.value = sleep_state;
  485. status = acpi_evaluate_object(NULL, METHOD_NAME__WAK, &arg_list, NULL);
  486. if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  487. ACPI_EXCEPTION((AE_INFO, status, "During Method _WAK"));
  488. }
  489. /* TBD: _WAK "sometimes" returns stuff - do we want to look at it? */
  490. /*
  491. * Some BIOSes assume that WAK_STS will be cleared on resume and use
  492. * it to determine whether the system is rebooting or resuming. Clear
  493. * it for compatibility.
  494. */
  495. acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, 1);
  496. acpi_gbl_system_awake_and_running = TRUE;
  497. /* Enable power button */
  498. (void)
  499. acpi_write_bit_register(acpi_gbl_fixed_event_info
  500. [ACPI_EVENT_POWER_BUTTON].
  501. enable_register_id, ACPI_ENABLE_EVENT);
  502. (void)
  503. acpi_write_bit_register(acpi_gbl_fixed_event_info
  504. [ACPI_EVENT_POWER_BUTTON].
  505. status_register_id, ACPI_CLEAR_STATUS);
  506. arg.integer.value = ACPI_SST_WORKING;
  507. status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
  508. if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
  509. ACPI_EXCEPTION((AE_INFO, status, "During Method _SST"));
  510. }
  511. return_ACPI_STATUS(status);
  512. }
  513. ACPI_EXPORT_SYMBOL(acpi_leave_sleep_state)