1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3 *
4 * Module Name: evgpeinit - System GPE initialization and update
5 *
6 * Copyright (C) 2000 - 2019, Intel Corp.
7 *
8 *****************************************************************************/
9
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acevents.h"
13 #include "acnamesp.h"
14
15 #define _COMPONENT ACPI_EVENTS
16 ACPI_MODULE_NAME("evgpeinit")
17 #if (!ACPI_REDUCED_HARDWARE) /* Entire module */
18 /*
19 * Note: History of _PRW support in ACPICA
20 *
21 * Originally (2000 - 2010), the GPE initialization code performed a walk of
22 * the entire namespace to execute the _PRW methods and detect all GPEs
23 * capable of waking the system.
24 *
25 * As of 10/2010, the _PRW method execution has been removed since it is
26 * actually unnecessary. The host OS must in fact execute all _PRW methods
27 * in order to identify the device/power-resource dependencies. We now put
28 * the onus on the host OS to identify the wake GPEs as part of this process
29 * and to inform ACPICA of these GPEs via the acpi_setup_gpe_for_wake interface. This
30 * not only reduces the complexity of the ACPICA initialization code, but in
31 * some cases (on systems with very large namespaces) it should reduce the
32 * kernel boot time as well.
33 */
34
35 /*******************************************************************************
36 *
37 * FUNCTION: acpi_ev_gpe_initialize
38 *
39 * PARAMETERS: None
40 *
41 * RETURN: Status
42 *
43 * DESCRIPTION: Initialize the GPE data structures and the FADT GPE 0/1 blocks
44 *
45 ******************************************************************************/
46 acpi_status acpi_ev_gpe_initialize(void)
47 {
48 u32 register_count0 = 0;
49 u32 register_count1 = 0;
50 u32 gpe_number_max = 0;
51 acpi_status status;
52
53 ACPI_FUNCTION_TRACE(ev_gpe_initialize);
54
55 ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
56 "Initializing General Purpose Events (GPEs):\n"));
57
58 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
59 if (ACPI_FAILURE(status)) {
60 return_ACPI_STATUS(status);
61 }
62
63 /*
64 * Initialize the GPE Block(s) defined in the FADT
65 *
66 * Why the GPE register block lengths are divided by 2: From the ACPI
67 * Spec, section "General-Purpose Event Registers", we have:
68 *
69 * "Each register block contains two registers of equal length
70 * GPEx_STS and GPEx_EN (where x is 0 or 1). The length of the
71 * GPE0_STS and GPE0_EN registers is equal to half the GPE0_LEN
72 * The length of the GPE1_STS and GPE1_EN registers is equal to
73 * half the GPE1_LEN. If a generic register block is not supported
74 * then its respective block pointer and block length values in the
75 * FADT table contain zeros. The GPE0_LEN and GPE1_LEN do not need
76 * to be the same size."
77 */
78
79 /*
80 * Determine the maximum GPE number for this machine.
81 *
82 * Note: both GPE0 and GPE1 are optional, and either can exist without
83 * the other.
84 *
85 * If EITHER the register length OR the block address are zero, then that
86 * particular block is not supported.
87 */
88 if (acpi_gbl_FADT.gpe0_block_length &&
89 acpi_gbl_FADT.xgpe0_block.address) {
90
91 /* GPE block 0 exists (has both length and address > 0) */
92
93 register_count0 = (u16)(acpi_gbl_FADT.gpe0_block_length / 2);
94 gpe_number_max =
95 (register_count0 * ACPI_GPE_REGISTER_WIDTH) - 1;
96
97 /* Install GPE Block 0 */
98
99 status = acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
100 acpi_gbl_FADT.xgpe0_block.
101 address,
102 acpi_gbl_FADT.xgpe0_block.
103 space_id, register_count0, 0,
104 acpi_gbl_FADT.sci_interrupt,
105 &acpi_gbl_gpe_fadt_blocks[0]);
106
107 if (ACPI_FAILURE(status)) {
108 ACPI_EXCEPTION((AE_INFO, status,
109 "Could not create GPE Block 0"));
110 }
111 }
112
113 if (acpi_gbl_FADT.gpe1_block_length &&
114 acpi_gbl_FADT.xgpe1_block.address) {
115
116 /* GPE block 1 exists (has both length and address > 0) */
117
118 register_count1 = (u16)(acpi_gbl_FADT.gpe1_block_length / 2);
119
120 /* Check for GPE0/GPE1 overlap (if both banks exist) */
121
122 if ((register_count0) &&
123 (gpe_number_max >= acpi_gbl_FADT.gpe1_base)) {
124 ACPI_ERROR((AE_INFO,
125 "GPE0 block (GPE 0 to %u) overlaps the GPE1 block "
126 "(GPE %u to %u) - Ignoring GPE1",
127 gpe_number_max, acpi_gbl_FADT.gpe1_base,
128 acpi_gbl_FADT.gpe1_base +
129 ((register_count1 *
130 ACPI_GPE_REGISTER_WIDTH) - 1)));
131
132 /* Ignore GPE1 block by setting the register count to zero */
133
134 register_count1 = 0;
135 } else {
136 /* Install GPE Block 1 */
137
138 status =
139 acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
140 acpi_gbl_FADT.xgpe1_block.
141 address,
142 acpi_gbl_FADT.xgpe1_block.
143 space_id, register_count1,
144 acpi_gbl_FADT.gpe1_base,
145 acpi_gbl_FADT.
146 sci_interrupt,
147 &acpi_gbl_gpe_fadt_blocks
148 [1]);
149
150 if (ACPI_FAILURE(status)) {
151 ACPI_EXCEPTION((AE_INFO, status,
152 "Could not create GPE Block 1"));
153 }
154
155 /*
156 * GPE0 and GPE1 do not have to be contiguous in the GPE number
157 * space. However, GPE0 always starts at GPE number zero.
158 */
159 gpe_number_max = acpi_gbl_FADT.gpe1_base +
160 ((register_count1 * ACPI_GPE_REGISTER_WIDTH) - 1);
161 }
162 }
163
164 /* Exit if there are no GPE registers */
165
166 if ((register_count0 + register_count1) == 0) {
167
168 /* GPEs are not required by ACPI, this is OK */
169
170 ACPI_DEBUG_PRINT((ACPI_DB_INIT,
171 "There are no GPE blocks defined in the FADT\n"));
172 status = AE_OK;
173 goto cleanup;
174 }
175
176 cleanup:
177 (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
178 return_ACPI_STATUS(AE_OK);
179 }
180
181 /*******************************************************************************
182 *
183 * FUNCTION: acpi_ev_update_gpes
184 *
185 * PARAMETERS: table_owner_id - ID of the newly-loaded ACPI table
186 *
187 * RETURN: None
188 *
189 * DESCRIPTION: Check for new GPE methods (_Lxx/_Exx) made available as a
190 * result of a Load() or load_table() operation. If new GPE
191 * methods have been installed, register the new methods.
192 *
193 ******************************************************************************/
194
195 void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
196 {
197 struct acpi_gpe_xrupt_info *gpe_xrupt_info;
198 struct acpi_gpe_block_info *gpe_block;
199 struct acpi_gpe_walk_info walk_info;
200 acpi_status status = AE_OK;
201
202 /*
203 * Find any _Lxx/_Exx GPE methods that have just been loaded.
204 *
205 * Any GPEs that correspond to new _Lxx/_Exx methods are immediately
206 * enabled.
207 *
208 * Examine the namespace underneath each gpe_device within the
209 * gpe_block lists.
210 */
211 status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
212 if (ACPI_FAILURE(status)) {
213 return;
214 }
215
216 walk_info.count = 0;
217 walk_info.owner_id = table_owner_id;
218 walk_info.execute_by_owner_id = TRUE;
219
220 /* Walk the interrupt level descriptor list */
221
222 gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
223 while (gpe_xrupt_info) {
224
225 /* Walk all Gpe Blocks attached to this interrupt level */
226
227 gpe_block = gpe_xrupt_info->gpe_block_list_head;
228 while (gpe_block) {
229 walk_info.gpe_block = gpe_block;
230 walk_info.gpe_device = gpe_block->node;
231
232 status = acpi_ns_walk_namespace(ACPI_TYPE_METHOD,
233 walk_info.gpe_device,
234 ACPI_UINT32_MAX,
235 ACPI_NS_WALK_NO_UNLOCK,
236 acpi_ev_match_gpe_method,
237 NULL, &walk_info, NULL);
238 if (ACPI_FAILURE(status)) {
239 ACPI_EXCEPTION((AE_INFO, status,
240 "While decoding _Lxx/_Exx methods"));
241 }
242
243 gpe_block = gpe_block->next;
244 }
245
246 gpe_xrupt_info = gpe_xrupt_info->next;
247 }
248
249 if (walk_info.count) {
250 ACPI_INFO(("Enabled %u new GPEs", walk_info.count));
251 }
252
253 (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
254 return;
255 }
256
257 /*******************************************************************************
258 *
259 * FUNCTION: acpi_ev_match_gpe_method
260 *
261 * PARAMETERS: Callback from walk_namespace
262 *
263 * RETURN: Status
264 *
265 * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
266 * control method under the _GPE portion of the namespace.
267 * Extract the name and GPE type from the object, saving this
268 * information for quick lookup during GPE dispatch. Allows a
269 * per-owner_id evaluation if execute_by_owner_id is TRUE in the
270 * walk_info parameter block.
271 *
272 * The name of each GPE control method is of the form:
273 * "_Lxx" or "_Exx", where:
274 * L - means that the GPE is level triggered
275 * E - means that the GPE is edge triggered
276 * xx - is the GPE number [in HEX]
277 *
278 * If walk_info->execute_by_owner_id is TRUE, we only execute examine GPE methods
279 * with that owner.
280 *
281 ******************************************************************************/
282
283 acpi_status
284 acpi_ev_match_gpe_method(acpi_handle obj_handle,
285 u32 level, void *context, void **return_value)
286 {
287 struct acpi_namespace_node *method_node =
288 ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
289 struct acpi_gpe_walk_info *walk_info =
290 ACPI_CAST_PTR(struct acpi_gpe_walk_info, context);
291 struct acpi_gpe_event_info *gpe_event_info;
292 acpi_status status;
293 u32 gpe_number;
294 u8 temp_gpe_number;
295 char name[ACPI_NAMESEG_SIZE + 1];
296 u8 type;
297
298 ACPI_FUNCTION_TRACE(ev_match_gpe_method);
299
300 /* Check if requested owner_id matches this owner_id */
301
302 if ((walk_info->execute_by_owner_id) &&
303 (method_node->owner_id != walk_info->owner_id)) {
304 return_ACPI_STATUS(AE_OK);
305 }
306
307 /*
308 * Match and decode the _Lxx and _Exx GPE method names
309 *
310 * 1) Extract the method name and null terminate it
311 */
312 ACPI_MOVE_32_TO_32(name, &method_node->name.integer);
313 name[ACPI_NAMESEG_SIZE] = 0;
314
315 /* 2) Name must begin with an underscore */
316
317 if (name[0] != '_') {
318 return_ACPI_STATUS(AE_OK); /* Ignore this method */
319 }
320
321 /*
322 * 3) Edge/Level determination is based on the 2nd character
323 * of the method name
324 */
325 switch (name[1]) {
326 case 'L':
327
328 type = ACPI_GPE_LEVEL_TRIGGERED;
329 break;
330
331 case 'E':
332
333 type = ACPI_GPE_EDGE_TRIGGERED;
334 break;
335
336 default:
337
338 /* Unknown method type, just ignore it */
339
340 ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
341 "Ignoring unknown GPE method type: %s "
342 "(name not of form _Lxx or _Exx)", name));
343 return_ACPI_STATUS(AE_OK);
344 }
345
346 /* 4) The last two characters of the name are the hex GPE Number */
347
348 status = acpi_ut_ascii_to_hex_byte(&name[2], &temp_gpe_number);
349 if (ACPI_FAILURE(status)) {
350
351 /* Conversion failed; invalid method, just ignore it */
352
353 ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
354 "Could not extract GPE number from name: %s "
355 "(name is not of form _Lxx or _Exx)", name));
356 return_ACPI_STATUS(AE_OK);
357 }
358
359 /* Ensure that we have a valid GPE number for this GPE block */
360
361 gpe_number = (u32)temp_gpe_number;
362 gpe_event_info =
363 acpi_ev_low_get_gpe_info(gpe_number, walk_info->gpe_block);
364 if (!gpe_event_info) {
365 /*
366 * This gpe_number is not valid for this GPE block, just ignore it.
367 * However, it may be valid for a different GPE block, since GPE0
368 * and GPE1 methods both appear under \_GPE.
369 */
370 return_ACPI_STATUS(AE_OK);
371 }
372
373 if ((ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
374 ACPI_GPE_DISPATCH_HANDLER) ||
375 (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
376 ACPI_GPE_DISPATCH_RAW_HANDLER)) {
377
378 /* If there is already a handler, ignore this GPE method */
379
380 return_ACPI_STATUS(AE_OK);
381 }
382
383 if (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
384 ACPI_GPE_DISPATCH_METHOD) {
385 /*
386 * If there is already a method, ignore this method. But check
387 * for a type mismatch (if both the _Lxx AND _Exx exist)
388 */
389 if (type != (gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK)) {
390 ACPI_ERROR((AE_INFO,
391 "For GPE 0x%.2X, found both _L%2.2X and _E%2.2X methods",
392 gpe_number, gpe_number, gpe_number));
393 }
394 return_ACPI_STATUS(AE_OK);
395 }
396
397 /* Disable the GPE in case it's been enabled already. */
398
399 (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
400
401 /*
402 * Add the GPE information from above to the gpe_event_info block for
403 * use during dispatch of this GPE.
404 */
405 gpe_event_info->flags &= ~(ACPI_GPE_DISPATCH_MASK);
406 gpe_event_info->flags |= (u8)(type | ACPI_GPE_DISPATCH_METHOD);
407 gpe_event_info->dispatch.method_node = method_node;
408
409 ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
410 "Registered GPE method %s as GPE number 0x%.2X\n",
411 name, gpe_number));
412 return_ACPI_STATUS(AE_OK);
413 }
414
415 #endif /* !ACPI_REDUCED_HARDWARE */