xref: /openbmc/linux/drivers/acpi/x86/s2idle.c (revision bbb774d9)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Architecture-specific ACPI-based support for suspend-to-idle.
4  *
5  * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
6  * Author: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
7  * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
8  *
9  * On platforms supporting the Low Power S0 Idle interface there is an ACPI
10  * device object with the PNP0D80 compatible device ID (System Power Management
11  * Controller) and a specific _DSM method under it.  That method, if present,
12  * can be used to indicate to the platform that the OS is transitioning into a
13  * low-power state in which certain types of activity are not desirable or that
14  * it is leaving such a state, which allows the platform to adjust its operation
15  * mode accordingly.
16  */
17 
18 #include <linux/acpi.h>
19 #include <linux/device.h>
20 #include <linux/suspend.h>
21 
22 #include "../sleep.h"
23 
24 #ifdef CONFIG_SUSPEND
25 
26 static bool sleep_no_lps0 __read_mostly;
27 module_param(sleep_no_lps0, bool, 0644);
28 MODULE_PARM_DESC(sleep_no_lps0, "Do not use the special LPS0 device interface");
29 
30 static const struct acpi_device_id lps0_device_ids[] = {
31 	{"PNP0D80", },
32 	{"", },
33 };
34 
35 /* Microsoft platform agnostic UUID */
36 #define ACPI_LPS0_DSM_UUID_MICROSOFT      "11e00d56-ce64-47ce-837b-1f898f9aa461"
37 
38 #define ACPI_LPS0_DSM_UUID	"c4eb40a0-6cd2-11e2-bcfd-0800200c9a66"
39 
40 #define ACPI_LPS0_GET_DEVICE_CONSTRAINTS	1
41 #define ACPI_LPS0_SCREEN_OFF	3
42 #define ACPI_LPS0_SCREEN_ON	4
43 #define ACPI_LPS0_ENTRY		5
44 #define ACPI_LPS0_EXIT		6
45 #define ACPI_LPS0_MS_ENTRY      7
46 #define ACPI_LPS0_MS_EXIT       8
47 
48 /* AMD */
49 #define ACPI_LPS0_DSM_UUID_AMD      "e3f32452-febc-43ce-9039-932122d37721"
50 #define ACPI_LPS0_ENTRY_AMD         2
51 #define ACPI_LPS0_EXIT_AMD          3
52 #define ACPI_LPS0_SCREEN_OFF_AMD    4
53 #define ACPI_LPS0_SCREEN_ON_AMD     5
54 
55 static acpi_handle lps0_device_handle;
56 static guid_t lps0_dsm_guid;
57 static int lps0_dsm_func_mask;
58 
59 static guid_t lps0_dsm_guid_microsoft;
60 static int lps0_dsm_func_mask_microsoft;
61 
62 /* Device constraint entry structure */
63 struct lpi_device_info {
64 	char *name;
65 	int enabled;
66 	union acpi_object *package;
67 };
68 
69 /* Constraint package structure */
70 struct lpi_device_constraint {
71 	int uid;
72 	int min_dstate;
73 	int function_states;
74 };
75 
76 struct lpi_constraints {
77 	acpi_handle handle;
78 	int min_dstate;
79 };
80 
81 /* AMD Constraint package structure */
82 struct lpi_device_constraint_amd {
83 	char *name;
84 	int enabled;
85 	int function_states;
86 	int min_dstate;
87 };
88 
89 static LIST_HEAD(lps0_s2idle_devops_head);
90 
91 static struct lpi_constraints *lpi_constraints_table;
92 static int lpi_constraints_table_size;
93 static int rev_id;
94 
95 static void lpi_device_get_constraints_amd(void)
96 {
97 	union acpi_object *out_obj;
98 	int i, j, k;
99 
100 	out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
101 					  rev_id, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
102 					  NULL, ACPI_TYPE_PACKAGE);
103 
104 	acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
105 			  out_obj ? "successful" : "failed");
106 
107 	if (!out_obj)
108 		return;
109 
110 	for (i = 0; i < out_obj->package.count; i++) {
111 		union acpi_object *package = &out_obj->package.elements[i];
112 
113 		if (package->type == ACPI_TYPE_PACKAGE) {
114 			lpi_constraints_table = kcalloc(package->package.count,
115 							sizeof(*lpi_constraints_table),
116 							GFP_KERNEL);
117 
118 			if (!lpi_constraints_table)
119 				goto free_acpi_buffer;
120 
121 			acpi_handle_debug(lps0_device_handle,
122 					  "LPI: constraints list begin:\n");
123 
124 			for (j = 0; j < package->package.count; ++j) {
125 				union acpi_object *info_obj = &package->package.elements[j];
126 				struct lpi_device_constraint_amd dev_info = {};
127 				struct lpi_constraints *list;
128 				acpi_status status;
129 
130 				for (k = 0; k < info_obj->package.count; ++k) {
131 					union acpi_object *obj = &info_obj->package.elements[k];
132 
133 					list = &lpi_constraints_table[lpi_constraints_table_size];
134 					list->min_dstate = -1;
135 
136 					switch (k) {
137 					case 0:
138 						dev_info.enabled = obj->integer.value;
139 						break;
140 					case 1:
141 						dev_info.name = obj->string.pointer;
142 						break;
143 					case 2:
144 						dev_info.function_states = obj->integer.value;
145 						break;
146 					case 3:
147 						dev_info.min_dstate = obj->integer.value;
148 						break;
149 					}
150 
151 					if (!dev_info.enabled || !dev_info.name ||
152 					    !dev_info.min_dstate)
153 						continue;
154 
155 					status = acpi_get_handle(NULL, dev_info.name,
156 								 &list->handle);
157 					if (ACPI_FAILURE(status))
158 						continue;
159 
160 					acpi_handle_debug(lps0_device_handle,
161 							  "Name:%s\n", dev_info.name);
162 
163 					list->min_dstate = dev_info.min_dstate;
164 
165 					if (list->min_dstate < 0) {
166 						acpi_handle_debug(lps0_device_handle,
167 								  "Incomplete constraint defined\n");
168 						continue;
169 					}
170 				}
171 				lpi_constraints_table_size++;
172 			}
173 		}
174 	}
175 
176 	acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
177 
178 free_acpi_buffer:
179 	ACPI_FREE(out_obj);
180 }
181 
182 static void lpi_device_get_constraints(void)
183 {
184 	union acpi_object *out_obj;
185 	int i;
186 
187 	out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
188 					  1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
189 					  NULL, ACPI_TYPE_PACKAGE);
190 
191 	acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
192 			  out_obj ? "successful" : "failed");
193 
194 	if (!out_obj)
195 		return;
196 
197 	lpi_constraints_table = kcalloc(out_obj->package.count,
198 					sizeof(*lpi_constraints_table),
199 					GFP_KERNEL);
200 	if (!lpi_constraints_table)
201 		goto free_acpi_buffer;
202 
203 	acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n");
204 
205 	for (i = 0; i < out_obj->package.count; i++) {
206 		struct lpi_constraints *constraint;
207 		acpi_status status;
208 		union acpi_object *package = &out_obj->package.elements[i];
209 		struct lpi_device_info info = { };
210 		int package_count = 0, j;
211 
212 		if (!package)
213 			continue;
214 
215 		for (j = 0; j < package->package.count; ++j) {
216 			union acpi_object *element =
217 					&(package->package.elements[j]);
218 
219 			switch (element->type) {
220 			case ACPI_TYPE_INTEGER:
221 				info.enabled = element->integer.value;
222 				break;
223 			case ACPI_TYPE_STRING:
224 				info.name = element->string.pointer;
225 				break;
226 			case ACPI_TYPE_PACKAGE:
227 				package_count = element->package.count;
228 				info.package = element->package.elements;
229 				break;
230 			}
231 		}
232 
233 		if (!info.enabled || !info.package || !info.name)
234 			continue;
235 
236 		constraint = &lpi_constraints_table[lpi_constraints_table_size];
237 
238 		status = acpi_get_handle(NULL, info.name, &constraint->handle);
239 		if (ACPI_FAILURE(status))
240 			continue;
241 
242 		acpi_handle_debug(lps0_device_handle,
243 				  "index:%d Name:%s\n", i, info.name);
244 
245 		constraint->min_dstate = -1;
246 
247 		for (j = 0; j < package_count; ++j) {
248 			union acpi_object *info_obj = &info.package[j];
249 			union acpi_object *cnstr_pkg;
250 			union acpi_object *obj;
251 			struct lpi_device_constraint dev_info;
252 
253 			switch (info_obj->type) {
254 			case ACPI_TYPE_INTEGER:
255 				/* version */
256 				break;
257 			case ACPI_TYPE_PACKAGE:
258 				if (info_obj->package.count < 2)
259 					break;
260 
261 				cnstr_pkg = info_obj->package.elements;
262 				obj = &cnstr_pkg[0];
263 				dev_info.uid = obj->integer.value;
264 				obj = &cnstr_pkg[1];
265 				dev_info.min_dstate = obj->integer.value;
266 
267 				acpi_handle_debug(lps0_device_handle,
268 					"uid:%d min_dstate:%s\n",
269 					dev_info.uid,
270 					acpi_power_state_string(dev_info.min_dstate));
271 
272 				constraint->min_dstate = dev_info.min_dstate;
273 				break;
274 			}
275 		}
276 
277 		if (constraint->min_dstate < 0) {
278 			acpi_handle_debug(lps0_device_handle,
279 					  "Incomplete constraint defined\n");
280 			continue;
281 		}
282 
283 		lpi_constraints_table_size++;
284 	}
285 
286 	acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
287 
288 free_acpi_buffer:
289 	ACPI_FREE(out_obj);
290 }
291 
292 static void lpi_check_constraints(void)
293 {
294 	int i;
295 
296 	for (i = 0; i < lpi_constraints_table_size; ++i) {
297 		acpi_handle handle = lpi_constraints_table[i].handle;
298 		struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
299 
300 		if (!adev)
301 			continue;
302 
303 		acpi_handle_debug(handle,
304 			"LPI: required min power state:%s current power state:%s\n",
305 			acpi_power_state_string(lpi_constraints_table[i].min_dstate),
306 			acpi_power_state_string(adev->power.state));
307 
308 		if (!adev->flags.power_manageable) {
309 			acpi_handle_info(handle, "LPI: Device not power manageable\n");
310 			lpi_constraints_table[i].handle = NULL;
311 			continue;
312 		}
313 
314 		if (adev->power.state < lpi_constraints_table[i].min_dstate)
315 			acpi_handle_info(handle,
316 				"LPI: Constraint not met; min power state:%s current power state:%s\n",
317 				acpi_power_state_string(lpi_constraints_table[i].min_dstate),
318 				acpi_power_state_string(adev->power.state));
319 	}
320 }
321 
322 static void acpi_sleep_run_lps0_dsm(unsigned int func, unsigned int func_mask, guid_t dsm_guid)
323 {
324 	union acpi_object *out_obj;
325 
326 	if (!(func_mask & (1 << func)))
327 		return;
328 
329 	out_obj = acpi_evaluate_dsm(lps0_device_handle, &dsm_guid,
330 					rev_id, func, NULL);
331 	ACPI_FREE(out_obj);
332 
333 	acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n",
334 			  func, out_obj ? "successful" : "failed");
335 }
336 
337 static bool acpi_s2idle_vendor_amd(void)
338 {
339 	return boot_cpu_data.x86_vendor == X86_VENDOR_AMD;
340 }
341 
342 static int validate_dsm(acpi_handle handle, const char *uuid, int rev, guid_t *dsm_guid)
343 {
344 	union acpi_object *obj;
345 	int ret = -EINVAL;
346 
347 	guid_parse(uuid, dsm_guid);
348 	obj = acpi_evaluate_dsm(handle, dsm_guid, rev, 0, NULL);
349 
350 	/* Check if the _DSM is present and as expected. */
351 	if (!obj || obj->type != ACPI_TYPE_BUFFER || obj->buffer.length == 0 ||
352 	    obj->buffer.length > sizeof(u32)) {
353 		acpi_handle_debug(handle,
354 				"_DSM UUID %s rev %d function 0 evaluation failed\n", uuid, rev);
355 		goto out;
356 	}
357 
358 	ret = *(int *)obj->buffer.pointer;
359 	acpi_handle_debug(handle, "_DSM UUID %s rev %d function mask: 0x%x\n", uuid, rev, ret);
360 
361 out:
362 	ACPI_FREE(obj);
363 	return ret;
364 }
365 
366 static int lps0_device_attach(struct acpi_device *adev,
367 			      const struct acpi_device_id *not_used)
368 {
369 	if (lps0_device_handle)
370 		return 0;
371 
372 	if (acpi_s2idle_vendor_amd()) {
373 		/* AMD0004, AMD0005, AMDI0005:
374 		 * - Should use rev_id 0x0
375 		 * - function mask > 0x3: Should use AMD method, but has off by one bug
376 		 * - function mask = 0x3: Should use Microsoft method
377 		 * AMDI0006:
378 		 * - should use rev_id 0x0
379 		 * - function mask = 0x3: Should use Microsoft method
380 		 * AMDI0007:
381 		 * - Should use rev_id 0x2
382 		 * - Should only use AMD method
383 		 */
384 		const char *hid = acpi_device_hid(adev);
385 		rev_id = strcmp(hid, "AMDI0007") ? 0 : 2;
386 		lps0_dsm_func_mask = validate_dsm(adev->handle,
387 					ACPI_LPS0_DSM_UUID_AMD, rev_id, &lps0_dsm_guid);
388 		lps0_dsm_func_mask_microsoft = validate_dsm(adev->handle,
389 					ACPI_LPS0_DSM_UUID_MICROSOFT, 0,
390 					&lps0_dsm_guid_microsoft);
391 		if (lps0_dsm_func_mask > 0x3 && (!strcmp(hid, "AMD0004") ||
392 						 !strcmp(hid, "AMD0005") ||
393 						 !strcmp(hid, "AMDI0005"))) {
394 			lps0_dsm_func_mask = (lps0_dsm_func_mask << 1) | 0x1;
395 			acpi_handle_debug(adev->handle, "_DSM UUID %s: Adjusted function mask: 0x%x\n",
396 					  ACPI_LPS0_DSM_UUID_AMD, lps0_dsm_func_mask);
397 		} else if (lps0_dsm_func_mask_microsoft > 0 &&
398 				(!strcmp(hid, "AMDI0007") ||
399 				 !strcmp(hid, "AMDI0008"))) {
400 			lps0_dsm_func_mask_microsoft = -EINVAL;
401 			acpi_handle_debug(adev->handle, "_DSM Using AMD method\n");
402 		}
403 	} else {
404 		rev_id = 1;
405 		lps0_dsm_func_mask = validate_dsm(adev->handle,
406 					ACPI_LPS0_DSM_UUID, rev_id, &lps0_dsm_guid);
407 		lps0_dsm_func_mask_microsoft = -EINVAL;
408 	}
409 
410 	if (lps0_dsm_func_mask < 0 && lps0_dsm_func_mask_microsoft < 0)
411 		return 0; //function evaluation failed
412 
413 	lps0_device_handle = adev->handle;
414 
415 	if (acpi_s2idle_vendor_amd())
416 		lpi_device_get_constraints_amd();
417 	else
418 		lpi_device_get_constraints();
419 
420 	/*
421 	 * Use suspend-to-idle by default if ACPI_FADT_LOW_POWER_S0 is set in
422 	 * the FADT and the default suspend mode was not set from the command
423 	 * line.
424 	 */
425 	if ((acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0) &&
426 	    mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3) {
427 		mem_sleep_current = PM_SUSPEND_TO_IDLE;
428 		pr_info("Low-power S0 idle used by default for system suspend\n");
429 	}
430 
431 	/*
432 	 * Some LPS0 systems, like ASUS Zenbook UX430UNR/i7-8550U, require the
433 	 * EC GPE to be enabled while suspended for certain wakeup devices to
434 	 * work, so mark it as wakeup-capable.
435 	 */
436 	acpi_ec_mark_gpe_for_wake();
437 
438 	return 0;
439 }
440 
441 static struct acpi_scan_handler lps0_handler = {
442 	.ids = lps0_device_ids,
443 	.attach = lps0_device_attach,
444 };
445 
446 int acpi_s2idle_prepare_late(void)
447 {
448 	struct acpi_s2idle_dev_ops *handler;
449 
450 	if (!lps0_device_handle || sleep_no_lps0)
451 		return 0;
452 
453 	if (pm_debug_messages_on)
454 		lpi_check_constraints();
455 
456 	/* Screen off */
457 	if (lps0_dsm_func_mask > 0)
458 		acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ?
459 					ACPI_LPS0_SCREEN_OFF_AMD :
460 					ACPI_LPS0_SCREEN_OFF,
461 					lps0_dsm_func_mask, lps0_dsm_guid);
462 
463 	if (lps0_dsm_func_mask_microsoft > 0)
464 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF,
465 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
466 
467 	/* LPS0 entry */
468 	if (lps0_dsm_func_mask > 0)
469 		acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ?
470 					ACPI_LPS0_ENTRY_AMD :
471 					ACPI_LPS0_ENTRY,
472 					lps0_dsm_func_mask, lps0_dsm_guid);
473 	if (lps0_dsm_func_mask_microsoft > 0) {
474 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY,
475 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
476 		/* modern standby entry */
477 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_MS_ENTRY,
478 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
479 	}
480 
481 	list_for_each_entry(handler, &lps0_s2idle_devops_head, list_node) {
482 		if (handler->prepare)
483 			handler->prepare();
484 	}
485 
486 	return 0;
487 }
488 
489 void acpi_s2idle_restore_early(void)
490 {
491 	struct acpi_s2idle_dev_ops *handler;
492 
493 	if (!lps0_device_handle || sleep_no_lps0)
494 		return;
495 
496 	list_for_each_entry(handler, &lps0_s2idle_devops_head, list_node)
497 		if (handler->restore)
498 			handler->restore();
499 
500 	/* Modern standby exit */
501 	if (lps0_dsm_func_mask_microsoft > 0)
502 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_MS_EXIT,
503 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
504 
505 	/* LPS0 exit */
506 	if (lps0_dsm_func_mask > 0)
507 		acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ?
508 					ACPI_LPS0_EXIT_AMD :
509 					ACPI_LPS0_EXIT,
510 					lps0_dsm_func_mask, lps0_dsm_guid);
511 	if (lps0_dsm_func_mask_microsoft > 0)
512 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT,
513 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
514 
515 	/* Screen on */
516 	if (lps0_dsm_func_mask_microsoft > 0)
517 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON,
518 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
519 	if (lps0_dsm_func_mask > 0)
520 		acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ?
521 					ACPI_LPS0_SCREEN_ON_AMD :
522 					ACPI_LPS0_SCREEN_ON,
523 					lps0_dsm_func_mask, lps0_dsm_guid);
524 }
525 
526 static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
527 	.begin = acpi_s2idle_begin,
528 	.prepare = acpi_s2idle_prepare,
529 	.prepare_late = acpi_s2idle_prepare_late,
530 	.wake = acpi_s2idle_wake,
531 	.restore_early = acpi_s2idle_restore_early,
532 	.restore = acpi_s2idle_restore,
533 	.end = acpi_s2idle_end,
534 };
535 
536 void acpi_s2idle_setup(void)
537 {
538 	acpi_scan_add_handler(&lps0_handler);
539 	s2idle_set_ops(&acpi_s2idle_ops_lps0);
540 }
541 
542 int acpi_register_lps0_dev(struct acpi_s2idle_dev_ops *arg)
543 {
544 	if (!lps0_device_handle || sleep_no_lps0)
545 		return -ENODEV;
546 
547 	lock_system_sleep();
548 	list_add(&arg->list_node, &lps0_s2idle_devops_head);
549 	unlock_system_sleep();
550 
551 	return 0;
552 }
553 EXPORT_SYMBOL_GPL(acpi_register_lps0_dev);
554 
555 void acpi_unregister_lps0_dev(struct acpi_s2idle_dev_ops *arg)
556 {
557 	if (!lps0_device_handle || sleep_no_lps0)
558 		return;
559 
560 	lock_system_sleep();
561 	list_del(&arg->list_node);
562 	unlock_system_sleep();
563 }
564 EXPORT_SYMBOL_GPL(acpi_unregister_lps0_dev);
565 
566 #endif /* CONFIG_SUSPEND */
567