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 - 2023, 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
16ACPI_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#ifdef ACPI_GPE_USE_LOGICAL_ADDRESSES
36#define ACPI_FADT_GPE_BLOCK_ADDRESS(N)	\
37	acpi_gbl_FADT.xgpe##N##_block.space_id == \
38					ACPI_ADR_SPACE_SYSTEM_MEMORY ? \
39		(u64)acpi_gbl_xgpe##N##_block_logical_address : \
40		acpi_gbl_FADT.xgpe##N##_block.address
41#else
42#define ACPI_FADT_GPE_BLOCK_ADDRESS(N)	acpi_gbl_FADT.xgpe##N##_block.address
43#endif		/* ACPI_GPE_USE_LOGICAL_ADDRESSES */
44
45/*******************************************************************************
46 *
47 * FUNCTION:    acpi_ev_gpe_initialize
48 *
49 * PARAMETERS:  None
50 *
51 * RETURN:      Status
52 *
53 * DESCRIPTION: Initialize the GPE data structures and the FADT GPE 0/1 blocks
54 *
55 ******************************************************************************/
56acpi_status acpi_ev_gpe_initialize(void)
57{
58	u32 register_count0 = 0;
59	u32 register_count1 = 0;
60	u32 gpe_number_max = 0;
61	acpi_status status;
62	u64 address;
63
64	ACPI_FUNCTION_TRACE(ev_gpe_initialize);
65
66	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
67			      "Initializing General Purpose Events (GPEs):\n"));
68
69	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
70	if (ACPI_FAILURE(status)) {
71		return_ACPI_STATUS(status);
72	}
73
74	/*
75	 * Initialize the GPE Block(s) defined in the FADT
76	 *
77	 * Why the GPE register block lengths are divided by 2:  From the ACPI
78	 * Spec, section "General-Purpose Event Registers", we have:
79	 *
80	 * "Each register block contains two registers of equal length
81	 *  GPEx_STS and GPEx_EN (where x is 0 or 1). The length of the
82	 *  GPE0_STS and GPE0_EN registers is equal to half the GPE0_LEN
83	 *  The length of the GPE1_STS and GPE1_EN registers is equal to
84	 *  half the GPE1_LEN. If a generic register block is not supported
85	 *  then its respective block pointer and block length values in the
86	 *  FADT table contain zeros. The GPE0_LEN and GPE1_LEN do not need
87	 *  to be the same size."
88	 */
89
90	/*
91	 * Determine the maximum GPE number for this machine.
92	 *
93	 * Note: both GPE0 and GPE1 are optional, and either can exist without
94	 * the other.
95	 *
96	 * If EITHER the register length OR the block address are zero, then that
97	 * particular block is not supported.
98	 */
99	address = ACPI_FADT_GPE_BLOCK_ADDRESS(0);
100
101	if (acpi_gbl_FADT.gpe0_block_length && address) {
102
103		/* GPE block 0 exists (has both length and address > 0) */
104
105		register_count0 = (u16)(acpi_gbl_FADT.gpe0_block_length / 2);
106		gpe_number_max =
107		    (register_count0 * ACPI_GPE_REGISTER_WIDTH) - 1;
108
109		/* Install GPE Block 0 */
110
111		status = acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
112						  address,
113						  acpi_gbl_FADT.xgpe0_block.
114						  space_id, register_count0, 0,
115						  acpi_gbl_FADT.sci_interrupt,
116						  &acpi_gbl_gpe_fadt_blocks[0]);
117
118		if (ACPI_FAILURE(status)) {
119			ACPI_EXCEPTION((AE_INFO, status,
120					"Could not create GPE Block 0"));
121		}
122	}
123
124	address = ACPI_FADT_GPE_BLOCK_ADDRESS(1);
125
126	if (acpi_gbl_FADT.gpe1_block_length && address) {
127
128		/* GPE block 1 exists (has both length and address > 0) */
129
130		register_count1 = (u16)(acpi_gbl_FADT.gpe1_block_length / 2);
131
132		/* Check for GPE0/GPE1 overlap (if both banks exist) */
133
134		if ((register_count0) &&
135		    (gpe_number_max >= acpi_gbl_FADT.gpe1_base)) {
136			ACPI_ERROR((AE_INFO,
137				    "GPE0 block (GPE 0 to %u) overlaps the GPE1 block "
138				    "(GPE %u to %u) - Ignoring GPE1",
139				    gpe_number_max, acpi_gbl_FADT.gpe1_base,
140				    acpi_gbl_FADT.gpe1_base +
141				    ((register_count1 *
142				      ACPI_GPE_REGISTER_WIDTH) - 1)));
143
144			/* Ignore GPE1 block by setting the register count to zero */
145
146			register_count1 = 0;
147		} else {
148			/* Install GPE Block 1 */
149
150			status =
151			    acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
152						     address,
153						     acpi_gbl_FADT.xgpe1_block.
154						     space_id, register_count1,
155						     acpi_gbl_FADT.gpe1_base,
156						     acpi_gbl_FADT.
157						     sci_interrupt,
158						     &acpi_gbl_gpe_fadt_blocks
159						     [1]);
160
161			if (ACPI_FAILURE(status)) {
162				ACPI_EXCEPTION((AE_INFO, status,
163						"Could not create GPE Block 1"));
164			}
165
166			/*
167			 * GPE0 and GPE1 do not have to be contiguous in the GPE number
168			 * space. However, GPE0 always starts at GPE number zero.
169			 */
170		}
171	}
172
173	/* Exit if there are no GPE registers */
174
175	if ((register_count0 + register_count1) == 0) {
176
177		/* GPEs are not required by ACPI, this is OK */
178
179		ACPI_DEBUG_PRINT((ACPI_DB_INIT,
180				  "There are no GPE blocks defined in the FADT\n"));
181		goto cleanup;
182	}
183
184cleanup:
185	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
186	return_ACPI_STATUS(AE_OK);
187}
188
189/*******************************************************************************
190 *
191 * FUNCTION:    acpi_ev_update_gpes
192 *
193 * PARAMETERS:  table_owner_id      - ID of the newly-loaded ACPI table
194 *
195 * RETURN:      None
196 *
197 * DESCRIPTION: Check for new GPE methods (_Lxx/_Exx) made available as a
198 *              result of a Load() or load_table() operation. If new GPE
199 *              methods have been installed, register the new methods.
200 *
201 ******************************************************************************/
202
203void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
204{
205	struct acpi_gpe_xrupt_info *gpe_xrupt_info;
206	struct acpi_gpe_block_info *gpe_block;
207	struct acpi_gpe_walk_info walk_info;
208	acpi_status status = AE_OK;
209
210	/*
211	 * Find any _Lxx/_Exx GPE methods that have just been loaded.
212	 *
213	 * Any GPEs that correspond to new _Lxx/_Exx methods are immediately
214	 * enabled.
215	 *
216	 * Examine the namespace underneath each gpe_device within the
217	 * gpe_block lists.
218	 */
219	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
220	if (ACPI_FAILURE(status)) {
221		return;
222	}
223
224	walk_info.count = 0;
225	walk_info.owner_id = table_owner_id;
226	walk_info.execute_by_owner_id = TRUE;
227
228	/* Walk the interrupt level descriptor list */
229
230	gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
231	while (gpe_xrupt_info) {
232
233		/* Walk all Gpe Blocks attached to this interrupt level */
234
235		gpe_block = gpe_xrupt_info->gpe_block_list_head;
236		while (gpe_block) {
237			walk_info.gpe_block = gpe_block;
238			walk_info.gpe_device = gpe_block->node;
239
240			status = acpi_ns_walk_namespace(ACPI_TYPE_METHOD,
241							walk_info.gpe_device,
242							ACPI_UINT32_MAX,
243							ACPI_NS_WALK_NO_UNLOCK,
244							acpi_ev_match_gpe_method,
245							NULL, &walk_info, NULL);
246			if (ACPI_FAILURE(status)) {
247				ACPI_EXCEPTION((AE_INFO, status,
248						"While decoding _Lxx/_Exx methods"));
249			}
250
251			gpe_block = gpe_block->next;
252		}
253
254		gpe_xrupt_info = gpe_xrupt_info->next;
255	}
256
257	if (walk_info.count) {
258		ACPI_INFO(("Enabled %u new GPEs", walk_info.count));
259	}
260
261	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
262	return;
263}
264
265/*******************************************************************************
266 *
267 * FUNCTION:    acpi_ev_match_gpe_method
268 *
269 * PARAMETERS:  Callback from walk_namespace
270 *
271 * RETURN:      Status
272 *
273 * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
274 *              control method under the _GPE portion of the namespace.
275 *              Extract the name and GPE type from the object, saving this
276 *              information for quick lookup during GPE dispatch. Allows a
277 *              per-owner_id evaluation if execute_by_owner_id is TRUE in the
278 *              walk_info parameter block.
279 *
280 *              The name of each GPE control method is of the form:
281 *              "_Lxx" or "_Exx", where:
282 *                  L      - means that the GPE is level triggered
283 *                  E      - means that the GPE is edge triggered
284 *                  xx     - is the GPE number [in HEX]
285 *
286 * If walk_info->execute_by_owner_id is TRUE, we only execute examine GPE methods
287 * with that owner.
288 *
289 ******************************************************************************/
290
291acpi_status
292acpi_ev_match_gpe_method(acpi_handle obj_handle,
293			 u32 level, void *context, void **return_value)
294{
295	struct acpi_namespace_node *method_node =
296	    ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
297	struct acpi_gpe_walk_info *walk_info =
298	    ACPI_CAST_PTR(struct acpi_gpe_walk_info, context);
299	struct acpi_gpe_event_info *gpe_event_info;
300	acpi_status status;
301	u32 gpe_number;
302	u8 temp_gpe_number;
303	char name[ACPI_NAMESEG_SIZE + 1];
304	u8 type;
305
306	ACPI_FUNCTION_TRACE(ev_match_gpe_method);
307
308	/* Check if requested owner_id matches this owner_id */
309
310	if ((walk_info->execute_by_owner_id) &&
311	    (method_node->owner_id != walk_info->owner_id)) {
312		return_ACPI_STATUS(AE_OK);
313	}
314
315	/*
316	 * Match and decode the _Lxx and _Exx GPE method names
317	 *
318	 * 1) Extract the method name and null terminate it
319	 */
320	ACPI_MOVE_32_TO_32(name, &method_node->name.integer);
321	name[ACPI_NAMESEG_SIZE] = 0;
322
323	/* 2) Name must begin with an underscore */
324
325	if (name[0] != '_') {
326		return_ACPI_STATUS(AE_OK);	/* Ignore this method */
327	}
328
329	/*
330	 * 3) Edge/Level determination is based on the 2nd character
331	 *    of the method name
332	 */
333	switch (name[1]) {
334	case 'L':
335
336		type = ACPI_GPE_LEVEL_TRIGGERED;
337		break;
338
339	case 'E':
340
341		type = ACPI_GPE_EDGE_TRIGGERED;
342		break;
343
344	default:
345
346		/* Unknown method type, just ignore it */
347
348		ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
349				  "Ignoring unknown GPE method type: %s "
350				  "(name not of form _Lxx or _Exx)", name));
351		return_ACPI_STATUS(AE_OK);
352	}
353
354	/* 4) The last two characters of the name are the hex GPE Number */
355
356	status = acpi_ut_ascii_to_hex_byte(&name[2], &temp_gpe_number);
357	if (ACPI_FAILURE(status)) {
358
359		/* Conversion failed; invalid method, just ignore it */
360
361		ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
362				  "Could not extract GPE number from name: %s "
363				  "(name is not of form _Lxx or _Exx)", name));
364		return_ACPI_STATUS(AE_OK);
365	}
366
367	/* Ensure that we have a valid GPE number for this GPE block */
368
369	gpe_number = (u32)temp_gpe_number;
370	gpe_event_info =
371	    acpi_ev_low_get_gpe_info(gpe_number, walk_info->gpe_block);
372	if (!gpe_event_info) {
373		/*
374		 * This gpe_number is not valid for this GPE block, just ignore it.
375		 * However, it may be valid for a different GPE block, since GPE0
376		 * and GPE1 methods both appear under \_GPE.
377		 */
378		return_ACPI_STATUS(AE_OK);
379	}
380
381	if ((ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
382	     ACPI_GPE_DISPATCH_HANDLER) ||
383	    (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
384	     ACPI_GPE_DISPATCH_RAW_HANDLER)) {
385
386		/* If there is already a handler, ignore this GPE method */
387
388		return_ACPI_STATUS(AE_OK);
389	}
390
391	if (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
392	    ACPI_GPE_DISPATCH_METHOD) {
393		/*
394		 * If there is already a method, ignore this method. But check
395		 * for a type mismatch (if both the _Lxx AND _Exx exist)
396		 */
397		if (type != (gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK)) {
398			ACPI_ERROR((AE_INFO,
399				    "For GPE 0x%.2X, found both _L%2.2X and _E%2.2X methods",
400				    gpe_number, gpe_number, gpe_number));
401		}
402		return_ACPI_STATUS(AE_OK);
403	}
404
405	/* Disable the GPE in case it's been enabled already. */
406
407	(void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
408
409	/*
410	 * Add the GPE information from above to the gpe_event_info block for
411	 * use during dispatch of this GPE.
412	 */
413	gpe_event_info->flags &= ~(ACPI_GPE_DISPATCH_MASK);
414	gpe_event_info->flags |= (u8)(type | ACPI_GPE_DISPATCH_METHOD);
415	gpe_event_info->dispatch.method_node = method_node;
416
417	ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
418			  "Registered GPE method %s as GPE number 0x%.2X\n",
419			  name, gpe_number));
420	return_ACPI_STATUS(AE_OK);
421}
422
423#endif				/* !ACPI_REDUCED_HARDWARE */
424