xref: /openbmc/linux/drivers/acpi/x86/s2idle.c (revision 56b5b1c7)
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 struct lpi_constraints *lpi_constraints_table;
90 static int lpi_constraints_table_size;
91 static int rev_id;
92 
93 static void lpi_device_get_constraints_amd(void)
94 {
95 	union acpi_object *out_obj;
96 	int i, j, k;
97 
98 	out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
99 					  rev_id, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
100 					  NULL, ACPI_TYPE_PACKAGE);
101 
102 	acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
103 			  out_obj ? "successful" : "failed");
104 
105 	if (!out_obj)
106 		return;
107 
108 	for (i = 0; i < out_obj->package.count; i++) {
109 		union acpi_object *package = &out_obj->package.elements[i];
110 
111 		if (package->type == ACPI_TYPE_PACKAGE) {
112 			lpi_constraints_table = kcalloc(package->package.count,
113 							sizeof(*lpi_constraints_table),
114 							GFP_KERNEL);
115 
116 			if (!lpi_constraints_table)
117 				goto free_acpi_buffer;
118 
119 			acpi_handle_debug(lps0_device_handle,
120 					  "LPI: constraints list begin:\n");
121 
122 			for (j = 0; j < package->package.count; ++j) {
123 				union acpi_object *info_obj = &package->package.elements[j];
124 				struct lpi_device_constraint_amd dev_info = {};
125 				struct lpi_constraints *list;
126 				acpi_status status;
127 
128 				for (k = 0; k < info_obj->package.count; ++k) {
129 					union acpi_object *obj = &info_obj->package.elements[k];
130 
131 					list = &lpi_constraints_table[lpi_constraints_table_size];
132 					list->min_dstate = -1;
133 
134 					switch (k) {
135 					case 0:
136 						dev_info.enabled = obj->integer.value;
137 						break;
138 					case 1:
139 						dev_info.name = obj->string.pointer;
140 						break;
141 					case 2:
142 						dev_info.function_states = obj->integer.value;
143 						break;
144 					case 3:
145 						dev_info.min_dstate = obj->integer.value;
146 						break;
147 					}
148 
149 					if (!dev_info.enabled || !dev_info.name ||
150 					    !dev_info.min_dstate)
151 						continue;
152 
153 					status = acpi_get_handle(NULL, dev_info.name,
154 								 &list->handle);
155 					if (ACPI_FAILURE(status))
156 						continue;
157 
158 					acpi_handle_debug(lps0_device_handle,
159 							  "Name:%s\n", dev_info.name);
160 
161 					list->min_dstate = dev_info.min_dstate;
162 
163 					if (list->min_dstate < 0) {
164 						acpi_handle_debug(lps0_device_handle,
165 								  "Incomplete constraint defined\n");
166 						continue;
167 					}
168 				}
169 				lpi_constraints_table_size++;
170 			}
171 		}
172 	}
173 
174 	acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
175 
176 free_acpi_buffer:
177 	ACPI_FREE(out_obj);
178 }
179 
180 static void lpi_device_get_constraints(void)
181 {
182 	union acpi_object *out_obj;
183 	int i;
184 
185 	out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
186 					  1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
187 					  NULL, ACPI_TYPE_PACKAGE);
188 
189 	acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
190 			  out_obj ? "successful" : "failed");
191 
192 	if (!out_obj)
193 		return;
194 
195 	lpi_constraints_table = kcalloc(out_obj->package.count,
196 					sizeof(*lpi_constraints_table),
197 					GFP_KERNEL);
198 	if (!lpi_constraints_table)
199 		goto free_acpi_buffer;
200 
201 	acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n");
202 
203 	for (i = 0; i < out_obj->package.count; i++) {
204 		struct lpi_constraints *constraint;
205 		acpi_status status;
206 		union acpi_object *package = &out_obj->package.elements[i];
207 		struct lpi_device_info info = { };
208 		int package_count = 0, j;
209 
210 		if (!package)
211 			continue;
212 
213 		for (j = 0; j < package->package.count; ++j) {
214 			union acpi_object *element =
215 					&(package->package.elements[j]);
216 
217 			switch (element->type) {
218 			case ACPI_TYPE_INTEGER:
219 				info.enabled = element->integer.value;
220 				break;
221 			case ACPI_TYPE_STRING:
222 				info.name = element->string.pointer;
223 				break;
224 			case ACPI_TYPE_PACKAGE:
225 				package_count = element->package.count;
226 				info.package = element->package.elements;
227 				break;
228 			}
229 		}
230 
231 		if (!info.enabled || !info.package || !info.name)
232 			continue;
233 
234 		constraint = &lpi_constraints_table[lpi_constraints_table_size];
235 
236 		status = acpi_get_handle(NULL, info.name, &constraint->handle);
237 		if (ACPI_FAILURE(status))
238 			continue;
239 
240 		acpi_handle_debug(lps0_device_handle,
241 				  "index:%d Name:%s\n", i, info.name);
242 
243 		constraint->min_dstate = -1;
244 
245 		for (j = 0; j < package_count; ++j) {
246 			union acpi_object *info_obj = &info.package[j];
247 			union acpi_object *cnstr_pkg;
248 			union acpi_object *obj;
249 			struct lpi_device_constraint dev_info;
250 
251 			switch (info_obj->type) {
252 			case ACPI_TYPE_INTEGER:
253 				/* version */
254 				break;
255 			case ACPI_TYPE_PACKAGE:
256 				if (info_obj->package.count < 2)
257 					break;
258 
259 				cnstr_pkg = info_obj->package.elements;
260 				obj = &cnstr_pkg[0];
261 				dev_info.uid = obj->integer.value;
262 				obj = &cnstr_pkg[1];
263 				dev_info.min_dstate = obj->integer.value;
264 
265 				acpi_handle_debug(lps0_device_handle,
266 					"uid:%d min_dstate:%s\n",
267 					dev_info.uid,
268 					acpi_power_state_string(dev_info.min_dstate));
269 
270 				constraint->min_dstate = dev_info.min_dstate;
271 				break;
272 			}
273 		}
274 
275 		if (constraint->min_dstate < 0) {
276 			acpi_handle_debug(lps0_device_handle,
277 					  "Incomplete constraint defined\n");
278 			continue;
279 		}
280 
281 		lpi_constraints_table_size++;
282 	}
283 
284 	acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
285 
286 free_acpi_buffer:
287 	ACPI_FREE(out_obj);
288 }
289 
290 static void lpi_check_constraints(void)
291 {
292 	int i;
293 
294 	for (i = 0; i < lpi_constraints_table_size; ++i) {
295 		acpi_handle handle = lpi_constraints_table[i].handle;
296 		struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
297 
298 		if (!adev)
299 			continue;
300 
301 		acpi_handle_debug(handle,
302 			"LPI: required min power state:%s current power state:%s\n",
303 			acpi_power_state_string(lpi_constraints_table[i].min_dstate),
304 			acpi_power_state_string(adev->power.state));
305 
306 		if (!adev->flags.power_manageable) {
307 			acpi_handle_info(handle, "LPI: Device not power manageable\n");
308 			lpi_constraints_table[i].handle = NULL;
309 			continue;
310 		}
311 
312 		if (adev->power.state < lpi_constraints_table[i].min_dstate)
313 			acpi_handle_info(handle,
314 				"LPI: Constraint not met; min power state:%s current power state:%s\n",
315 				acpi_power_state_string(lpi_constraints_table[i].min_dstate),
316 				acpi_power_state_string(adev->power.state));
317 	}
318 }
319 
320 static void acpi_sleep_run_lps0_dsm(unsigned int func, unsigned int func_mask, guid_t dsm_guid)
321 {
322 	union acpi_object *out_obj;
323 
324 	if (!(func_mask & (1 << func)))
325 		return;
326 
327 	out_obj = acpi_evaluate_dsm(lps0_device_handle, &dsm_guid,
328 					rev_id, func, NULL);
329 	ACPI_FREE(out_obj);
330 
331 	acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n",
332 			  func, out_obj ? "successful" : "failed");
333 }
334 
335 static bool acpi_s2idle_vendor_amd(void)
336 {
337 	return boot_cpu_data.x86_vendor == X86_VENDOR_AMD;
338 }
339 
340 static int validate_dsm(acpi_handle handle, const char *uuid, int rev, guid_t *dsm_guid)
341 {
342 	union acpi_object *obj;
343 	int ret = -EINVAL;
344 
345 	guid_parse(uuid, dsm_guid);
346 	obj = acpi_evaluate_dsm(handle, dsm_guid, rev, 0, NULL);
347 
348 	/* Check if the _DSM is present and as expected. */
349 	if (!obj || obj->type != ACPI_TYPE_BUFFER || obj->buffer.length == 0 ||
350 	    obj->buffer.length > sizeof(u32)) {
351 		acpi_handle_debug(handle,
352 				"_DSM UUID %s rev %d function 0 evaluation failed\n", uuid, rev);
353 		goto out;
354 	}
355 
356 	ret = *(int *)obj->buffer.pointer;
357 	acpi_handle_debug(handle, "_DSM UUID %s rev %d function mask: 0x%x\n", uuid, rev, ret);
358 
359 out:
360 	ACPI_FREE(obj);
361 	return ret;
362 }
363 
364 static int lps0_device_attach(struct acpi_device *adev,
365 			      const struct acpi_device_id *not_used)
366 {
367 	if (lps0_device_handle)
368 		return 0;
369 
370 	if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
371 		return 0;
372 
373 	if (acpi_s2idle_vendor_amd()) {
374 		/* AMD0004, AMD0005, AMDI0005:
375 		 * - Should use rev_id 0x0
376 		 * - function mask > 0x3: Should use AMD method, but has off by one bug
377 		 * - function mask = 0x3: Should use Microsoft method
378 		 * AMDI0006:
379 		 * - should use rev_id 0x0
380 		 * - function mask = 0x3: Should use Microsoft method
381 		 * AMDI0007:
382 		 * - Should use rev_id 0x2
383 		 * - Should only use AMD method
384 		 */
385 		const char *hid = acpi_device_hid(adev);
386 		rev_id = strcmp(hid, "AMDI0007") ? 0 : 2;
387 		lps0_dsm_func_mask = validate_dsm(adev->handle,
388 					ACPI_LPS0_DSM_UUID_AMD, rev_id, &lps0_dsm_guid);
389 		lps0_dsm_func_mask_microsoft = validate_dsm(adev->handle,
390 					ACPI_LPS0_DSM_UUID_MICROSOFT, 0,
391 					&lps0_dsm_guid_microsoft);
392 		if (lps0_dsm_func_mask > 0x3 && (!strcmp(hid, "AMD0004") ||
393 						 !strcmp(hid, "AMD0005") ||
394 						 !strcmp(hid, "AMDI0005"))) {
395 			lps0_dsm_func_mask = (lps0_dsm_func_mask << 1) | 0x1;
396 			acpi_handle_debug(adev->handle, "_DSM UUID %s: Adjusted function mask: 0x%x\n",
397 					  ACPI_LPS0_DSM_UUID_AMD, lps0_dsm_func_mask);
398 		} else if (lps0_dsm_func_mask_microsoft > 0 && !strcmp(hid, "AMDI0007")) {
399 			lps0_dsm_func_mask_microsoft = -EINVAL;
400 			acpi_handle_debug(adev->handle, "_DSM Using AMD method\n");
401 		}
402 	} else {
403 		rev_id = 1;
404 		lps0_dsm_func_mask = validate_dsm(adev->handle,
405 					ACPI_LPS0_DSM_UUID, rev_id, &lps0_dsm_guid);
406 		lps0_dsm_func_mask_microsoft = -EINVAL;
407 	}
408 
409 	if (lps0_dsm_func_mask < 0 && lps0_dsm_func_mask_microsoft < 0)
410 		return 0; //function evaluation failed
411 
412 	lps0_device_handle = adev->handle;
413 
414 	if (acpi_s2idle_vendor_amd())
415 		lpi_device_get_constraints_amd();
416 	else
417 		lpi_device_get_constraints();
418 
419 	/*
420 	 * Use suspend-to-idle by default if the default suspend mode was not
421 	 * set from the command line.
422 	 */
423 	if (mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3)
424 		mem_sleep_current = PM_SUSPEND_TO_IDLE;
425 
426 	/*
427 	 * Some LPS0 systems, like ASUS Zenbook UX430UNR/i7-8550U, require the
428 	 * EC GPE to be enabled while suspended for certain wakeup devices to
429 	 * work, so mark it as wakeup-capable.
430 	 */
431 	acpi_ec_mark_gpe_for_wake();
432 
433 	return 0;
434 }
435 
436 static struct acpi_scan_handler lps0_handler = {
437 	.ids = lps0_device_ids,
438 	.attach = lps0_device_attach,
439 };
440 
441 int acpi_s2idle_prepare_late(void)
442 {
443 	if (!lps0_device_handle || sleep_no_lps0)
444 		return 0;
445 
446 	if (pm_debug_messages_on)
447 		lpi_check_constraints();
448 
449 	/* Screen off */
450 	if (lps0_dsm_func_mask > 0)
451 		acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ?
452 					ACPI_LPS0_SCREEN_OFF_AMD :
453 					ACPI_LPS0_SCREEN_OFF,
454 					lps0_dsm_func_mask, lps0_dsm_guid);
455 
456 	if (lps0_dsm_func_mask_microsoft > 0)
457 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF,
458 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
459 
460 	/* LPS0 entry */
461 	if (lps0_dsm_func_mask > 0)
462 		acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ?
463 					ACPI_LPS0_ENTRY_AMD :
464 					ACPI_LPS0_ENTRY,
465 					lps0_dsm_func_mask, lps0_dsm_guid);
466 	if (lps0_dsm_func_mask_microsoft > 0) {
467 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY,
468 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
469 		/* modern standby entry */
470 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_MS_ENTRY,
471 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
472 	}
473 	return 0;
474 }
475 
476 void acpi_s2idle_restore_early(void)
477 {
478 	if (!lps0_device_handle || sleep_no_lps0)
479 		return;
480 
481 	/* Modern standby exit */
482 	if (lps0_dsm_func_mask_microsoft > 0)
483 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_MS_EXIT,
484 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
485 
486 	/* LPS0 exit */
487 	if (lps0_dsm_func_mask > 0)
488 		acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ?
489 					ACPI_LPS0_EXIT_AMD :
490 					ACPI_LPS0_EXIT,
491 					lps0_dsm_func_mask, lps0_dsm_guid);
492 	if (lps0_dsm_func_mask_microsoft > 0)
493 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT,
494 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
495 
496 	/* Screen on */
497 	if (lps0_dsm_func_mask_microsoft > 0)
498 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON,
499 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
500 	if (lps0_dsm_func_mask > 0)
501 		acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ?
502 					ACPI_LPS0_SCREEN_ON_AMD :
503 					ACPI_LPS0_SCREEN_ON,
504 					lps0_dsm_func_mask, lps0_dsm_guid);
505 }
506 
507 static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
508 	.begin = acpi_s2idle_begin,
509 	.prepare = acpi_s2idle_prepare,
510 	.prepare_late = acpi_s2idle_prepare_late,
511 	.wake = acpi_s2idle_wake,
512 	.restore_early = acpi_s2idle_restore_early,
513 	.restore = acpi_s2idle_restore,
514 	.end = acpi_s2idle_end,
515 };
516 
517 void acpi_s2idle_setup(void)
518 {
519 	acpi_scan_add_handler(&lps0_handler);
520 	s2idle_set_ops(&acpi_s2idle_ops_lps0);
521 }
522 
523 #endif /* CONFIG_SUSPEND */
524