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 #define ACPI_LPS0_DSM_UUID "c4eb40a0-6cd2-11e2-bcfd-0800200c9a66"
36
37 #define ACPI_LPS0_GET_DEVICE_CONSTRAINTS 1
38 #define ACPI_LPS0_SCREEN_OFF 3
39 #define ACPI_LPS0_SCREEN_ON 4
40 #define ACPI_LPS0_ENTRY 5
41 #define ACPI_LPS0_EXIT 6
42
43 /* AMD */
44 #define ACPI_LPS0_DSM_UUID_AMD "e3f32452-febc-43ce-9039-932122d37721"
45 #define ACPI_LPS0_SCREEN_OFF_AMD 4
46 #define ACPI_LPS0_SCREEN_ON_AMD 5
47
48 static acpi_handle lps0_device_handle;
49 static guid_t lps0_dsm_guid;
50 static char lps0_dsm_func_mask;
51
52 /* Device constraint entry structure */
53 struct lpi_device_info {
54 char *name;
55 int enabled;
56 union acpi_object *package;
57 };
58
59 /* Constraint package structure */
60 struct lpi_device_constraint {
61 int uid;
62 int min_dstate;
63 int function_states;
64 };
65
66 struct lpi_constraints {
67 acpi_handle handle;
68 int min_dstate;
69 };
70
71 /* AMD */
72 /* Device constraint entry structure */
73 struct lpi_device_info_amd {
74 int revision;
75 int count;
76 union acpi_object *package;
77 };
78
79 /* Constraint package structure */
80 struct lpi_device_constraint_amd {
81 char *name;
82 int enabled;
83 int function_states;
84 int min_dstate;
85 };
86
87 static struct lpi_constraints *lpi_constraints_table;
88 static int lpi_constraints_table_size;
89 static int rev_id;
90
lpi_device_get_constraints_amd(void)91 static void lpi_device_get_constraints_amd(void)
92 {
93 union acpi_object *out_obj;
94 int i, j, k;
95
96 out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
97 1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
98 NULL, ACPI_TYPE_PACKAGE);
99
100 if (!out_obj)
101 return;
102
103 acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
104 out_obj ? "successful" : "failed");
105
106 for (i = 0; i < out_obj->package.count; i++) {
107 union acpi_object *package = &out_obj->package.elements[i];
108
109 if (package->type == ACPI_TYPE_PACKAGE) {
110 lpi_constraints_table = kcalloc(package->package.count,
111 sizeof(*lpi_constraints_table),
112 GFP_KERNEL);
113
114 if (!lpi_constraints_table)
115 goto free_acpi_buffer;
116
117 acpi_handle_debug(lps0_device_handle,
118 "LPI: constraints list begin:\n");
119
120 for (j = 0; j < package->package.count; ++j) {
121 union acpi_object *info_obj = &package->package.elements[j];
122 struct lpi_device_constraint_amd dev_info = {};
123 struct lpi_constraints *list;
124 acpi_status status;
125
126 for (k = 0; k < info_obj->package.count; ++k) {
127 union acpi_object *obj = &info_obj->package.elements[k];
128
129 list = &lpi_constraints_table[lpi_constraints_table_size];
130 list->min_dstate = -1;
131
132 switch (k) {
133 case 0:
134 dev_info.enabled = obj->integer.value;
135 break;
136 case 1:
137 dev_info.name = obj->string.pointer;
138 break;
139 case 2:
140 dev_info.function_states = obj->integer.value;
141 break;
142 case 3:
143 dev_info.min_dstate = obj->integer.value;
144 break;
145 }
146
147 if (!dev_info.enabled || !dev_info.name ||
148 !dev_info.min_dstate)
149 continue;
150
151 status = acpi_get_handle(NULL, dev_info.name,
152 &list->handle);
153 if (ACPI_FAILURE(status))
154 continue;
155
156 acpi_handle_debug(lps0_device_handle,
157 "Name:%s\n", dev_info.name);
158
159 list->min_dstate = dev_info.min_dstate;
160
161 if (list->min_dstate < 0) {
162 acpi_handle_debug(lps0_device_handle,
163 "Incomplete constraint defined\n");
164 continue;
165 }
166 }
167 lpi_constraints_table_size++;
168 }
169 }
170 }
171
172 acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
173
174 free_acpi_buffer:
175 ACPI_FREE(out_obj);
176 }
177
lpi_device_get_constraints(void)178 static void lpi_device_get_constraints(void)
179 {
180 union acpi_object *out_obj;
181 int i;
182
183 out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
184 1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
185 NULL, ACPI_TYPE_PACKAGE);
186
187 acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
188 out_obj ? "successful" : "failed");
189
190 if (!out_obj)
191 return;
192
193 lpi_constraints_table = kcalloc(out_obj->package.count,
194 sizeof(*lpi_constraints_table),
195 GFP_KERNEL);
196 if (!lpi_constraints_table)
197 goto free_acpi_buffer;
198
199 acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n");
200
201 for (i = 0; i < out_obj->package.count; i++) {
202 struct lpi_constraints *constraint;
203 acpi_status status;
204 union acpi_object *package = &out_obj->package.elements[i];
205 struct lpi_device_info info = { };
206 int package_count = 0, j;
207
208 if (!package)
209 continue;
210
211 for (j = 0; j < package->package.count; ++j) {
212 union acpi_object *element =
213 &(package->package.elements[j]);
214
215 switch (element->type) {
216 case ACPI_TYPE_INTEGER:
217 info.enabled = element->integer.value;
218 break;
219 case ACPI_TYPE_STRING:
220 info.name = element->string.pointer;
221 break;
222 case ACPI_TYPE_PACKAGE:
223 package_count = element->package.count;
224 info.package = element->package.elements;
225 break;
226 }
227 }
228
229 if (!info.enabled || !info.package || !info.name)
230 continue;
231
232 constraint = &lpi_constraints_table[lpi_constraints_table_size];
233
234 status = acpi_get_handle(NULL, info.name, &constraint->handle);
235 if (ACPI_FAILURE(status))
236 continue;
237
238 acpi_handle_debug(lps0_device_handle,
239 "index:%d Name:%s\n", i, info.name);
240
241 constraint->min_dstate = -1;
242
243 for (j = 0; j < package_count; ++j) {
244 union acpi_object *info_obj = &info.package[j];
245 union acpi_object *cnstr_pkg;
246 union acpi_object *obj;
247 struct lpi_device_constraint dev_info;
248
249 switch (info_obj->type) {
250 case ACPI_TYPE_INTEGER:
251 /* version */
252 break;
253 case ACPI_TYPE_PACKAGE:
254 if (info_obj->package.count < 2)
255 break;
256
257 cnstr_pkg = info_obj->package.elements;
258 obj = &cnstr_pkg[0];
259 dev_info.uid = obj->integer.value;
260 obj = &cnstr_pkg[1];
261 dev_info.min_dstate = obj->integer.value;
262
263 acpi_handle_debug(lps0_device_handle,
264 "uid:%d min_dstate:%s\n",
265 dev_info.uid,
266 acpi_power_state_string(dev_info.min_dstate));
267
268 constraint->min_dstate = dev_info.min_dstate;
269 break;
270 }
271 }
272
273 if (constraint->min_dstate < 0) {
274 acpi_handle_debug(lps0_device_handle,
275 "Incomplete constraint defined\n");
276 continue;
277 }
278
279 lpi_constraints_table_size++;
280 }
281
282 acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
283
284 free_acpi_buffer:
285 ACPI_FREE(out_obj);
286 }
287
lpi_check_constraints(void)288 static void lpi_check_constraints(void)
289 {
290 int i;
291
292 for (i = 0; i < lpi_constraints_table_size; ++i) {
293 acpi_handle handle = lpi_constraints_table[i].handle;
294 struct acpi_device *adev;
295
296 if (!handle || acpi_bus_get_device(handle, &adev))
297 continue;
298
299 acpi_handle_debug(handle,
300 "LPI: required min power state:%s current power state:%s\n",
301 acpi_power_state_string(lpi_constraints_table[i].min_dstate),
302 acpi_power_state_string(adev->power.state));
303
304 if (!adev->flags.power_manageable) {
305 acpi_handle_info(handle, "LPI: Device not power manageable\n");
306 lpi_constraints_table[i].handle = NULL;
307 continue;
308 }
309
310 if (adev->power.state < lpi_constraints_table[i].min_dstate)
311 acpi_handle_info(handle,
312 "LPI: Constraint not met; min power state:%s current power state:%s\n",
313 acpi_power_state_string(lpi_constraints_table[i].min_dstate),
314 acpi_power_state_string(adev->power.state));
315 }
316 }
317
acpi_sleep_run_lps0_dsm(unsigned int func)318 static void acpi_sleep_run_lps0_dsm(unsigned int func)
319 {
320 union acpi_object *out_obj;
321
322 if (!(lps0_dsm_func_mask & (1 << func)))
323 return;
324
325 out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, rev_id, func, NULL);
326 ACPI_FREE(out_obj);
327
328 acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n",
329 func, out_obj ? "successful" : "failed");
330 }
331
acpi_s2idle_vendor_amd(void)332 static bool acpi_s2idle_vendor_amd(void)
333 {
334 return boot_cpu_data.x86_vendor == X86_VENDOR_AMD;
335 }
336
lps0_device_attach(struct acpi_device * adev,const struct acpi_device_id * not_used)337 static int lps0_device_attach(struct acpi_device *adev,
338 const struct acpi_device_id *not_used)
339 {
340 union acpi_object *out_obj;
341
342 if (lps0_device_handle)
343 return 0;
344
345 if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
346 return 0;
347
348 if (acpi_s2idle_vendor_amd()) {
349 guid_parse(ACPI_LPS0_DSM_UUID_AMD, &lps0_dsm_guid);
350 out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 0, 0, NULL);
351 rev_id = 0;
352 } else {
353 guid_parse(ACPI_LPS0_DSM_UUID, &lps0_dsm_guid);
354 out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 1, 0, NULL);
355 rev_id = 1;
356 }
357
358 /* Check if the _DSM is present and as expected. */
359 if (!out_obj || out_obj->type != ACPI_TYPE_BUFFER) {
360 acpi_handle_debug(adev->handle,
361 "_DSM function 0 evaluation failed\n");
362 return 0;
363 }
364
365 lps0_dsm_func_mask = *(char *)out_obj->buffer.pointer;
366
367 ACPI_FREE(out_obj);
368
369 acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n",
370 lps0_dsm_func_mask);
371
372 lps0_device_handle = adev->handle;
373
374 if (acpi_s2idle_vendor_amd())
375 lpi_device_get_constraints_amd();
376 else
377 lpi_device_get_constraints();
378
379 /*
380 * Use suspend-to-idle by default if the default suspend mode was not
381 * set from the command line.
382 */
383 if (mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3)
384 mem_sleep_current = PM_SUSPEND_TO_IDLE;
385
386 /*
387 * Some LPS0 systems, like ASUS Zenbook UX430UNR/i7-8550U, require the
388 * EC GPE to be enabled while suspended for certain wakeup devices to
389 * work, so mark it as wakeup-capable.
390 */
391 acpi_ec_mark_gpe_for_wake();
392
393 return 0;
394 }
395
396 static struct acpi_scan_handler lps0_handler = {
397 .ids = lps0_device_ids,
398 .attach = lps0_device_attach,
399 };
400
acpi_s2idle_prepare_late(void)401 int acpi_s2idle_prepare_late(void)
402 {
403 if (!lps0_device_handle || sleep_no_lps0)
404 return 0;
405
406 if (pm_debug_messages_on)
407 lpi_check_constraints();
408
409 if (acpi_s2idle_vendor_amd()) {
410 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF_AMD);
411 } else {
412 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF);
413 acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY);
414 }
415
416 return 0;
417 }
418
acpi_s2idle_restore_early(void)419 void acpi_s2idle_restore_early(void)
420 {
421 if (!lps0_device_handle || sleep_no_lps0)
422 return;
423
424 if (acpi_s2idle_vendor_amd()) {
425 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON_AMD);
426 } else {
427 acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT);
428 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON);
429 }
430 }
431
432 static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
433 .begin = acpi_s2idle_begin,
434 .prepare = acpi_s2idle_prepare,
435 .prepare_late = acpi_s2idle_prepare_late,
436 .wake = acpi_s2idle_wake,
437 .restore_early = acpi_s2idle_restore_early,
438 .restore = acpi_s2idle_restore,
439 .end = acpi_s2idle_end,
440 };
441
acpi_s2idle_setup(void)442 void acpi_s2idle_setup(void)
443 {
444 acpi_scan_add_handler(&lps0_handler);
445 s2idle_set_ops(&acpi_s2idle_ops_lps0);
446 }
447
448 #endif /* CONFIG_SUSPEND */
449