// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: evgpeinit - System GPE initialization and update
*
* Copyright (C) 2000 - 2025, Intel Corp.
*
*****************************************************************************/
#include <acpi/acpi.h>
#include "accommon.h"
#include "acevents.h"
#include "acnamesp.h"
#define _COMPONENT ACPI_EVENTS
ACPI_MODULE_NAME(
"evgpeinit")
#if (!ACPI_REDUCED_HARDWARE)
/* Entire module */
/*
* Note: History of _PRW support in ACPICA
*
* Originally (2000 - 2010), the GPE initialization code performed a walk of
* the entire namespace to execute the _PRW methods and detect all GPEs
* capable of waking the system.
*
* As of 10/2010, the _PRW method execution has been removed since it is
* actually unnecessary. The host OS must in fact execute all _PRW methods
* in order to identify the device/power-resource dependencies. We now put
* the onus on the host OS to identify the wake GPEs as part of this process
* and to inform ACPICA of these GPEs via the acpi_setup_gpe_for_wake interface. This
* not only reduces the complexity of the ACPICA initialization code, but in
* some cases (on systems with very large namespaces) it should reduce the
* kernel boot time as well.
*/
#ifdef ACPI_GPE_USE_LOGICAL_ADDRESSES
#define ACPI_FADT_GPE_BLOCK_ADDRESS(N) \
acpi_gbl_FADT.xgpe
##N
##_block.space_id == \
ACPI_ADR_SPACE_SYSTEM_MEMORY ? \
(u64)acpi_gbl_xgpe
##N
##_block_logical_address : \
acpi_gbl_FADT.xgpe
##N
##_block.address
#else
#define ACPI_FADT_GPE_BLOCK_ADDRESS(N) acpi_gbl_FADT.xgpe
##N
##_block.address
#endif /* ACPI_GPE_USE_LOGICAL_ADDRESSES */
/*******************************************************************************
*
* FUNCTION: acpi_ev_gpe_initialize
*
* PARAMETERS: None
*
* RETURN: Status
*
* DESCRIPTION: Initialize the GPE data structures and the FADT GPE 0/1 blocks
*
******************************************************************************/
acpi_status acpi_ev_gpe_initialize(
void)
{
u32 register_count0 = 0;
u32 register_count1 = 0;
u32 gpe_number_max = 0;
acpi_status status;
u64 address;
ACPI_FUNCTION_TRACE(ev_gpe_initialize);
ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
"Initializing General Purpose Events (GPEs):\n"));
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* Initialize the GPE Block(s) defined in the FADT
*
* Why the GPE register block lengths are divided by 2: From the ACPI
* Spec, section "General-Purpose Event Registers", we have:
*
* "Each register block contains two registers of equal length
* GPEx_STS and GPEx_EN (where x is 0 or 1). The length of the
* GPE0_STS and GPE0_EN registers is equal to half the GPE0_LEN
* The length of the GPE1_STS and GPE1_EN registers is equal to
* half the GPE1_LEN. If a generic register block is not supported
* then its respective block pointer and block length values in the
* FADT table contain zeros. The GPE0_LEN and GPE1_LEN do not need
* to be the same size."
*/
/*
* Determine the maximum GPE number for this machine.
*
* Note: both GPE0 and GPE1 are optional, and either can exist without
* the other.
*
* If EITHER the register length OR the block address are zero, then that
* particular block is not supported.
*/
address = ACPI_FADT_GPE_BLOCK_ADDRESS(0);
if (acpi_gbl_FADT.gpe0_block_length && address) {
/* GPE block 0 exists (has both length and address > 0) */
register_count0 = (u16)(acpi_gbl_FADT.gpe0_block_length / 2);
gpe_number_max =
(register_count0 * ACPI_GPE_REGISTER_WIDTH) - 1;
/* Install GPE Block 0 */
status = acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
address,
acpi_gbl_FADT.xgpe0_block.
space_id, register_count0, 0,
acpi_gbl_FADT.sci_interrupt,
&acpi_gbl_gpe_fadt_blocks[0]);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"Could not create GPE Block 0"));
}
}
address = ACPI_FADT_GPE_BLOCK_ADDRESS(1);
if (acpi_gbl_FADT.gpe1_block_length && address) {
/* GPE block 1 exists (has both length and address > 0) */
register_count1 = (u16)(acpi_gbl_FADT.gpe1_block_length / 2);
/* Check for GPE0/GPE1 overlap (if both banks exist) */
if ((register_count0) &&
(gpe_number_max >= acpi_gbl_FADT.gpe1_base)) {
ACPI_ERROR((AE_INFO,
"GPE0 block (GPE 0 to %u) overlaps the GPE1 block "
"(GPE %u to %u) - Ignoring GPE1",
gpe_number_max, acpi_gbl_FADT.gpe1_base,
acpi_gbl_FADT.gpe1_base +
((register_count1 *
ACPI_GPE_REGISTER_WIDTH) - 1)));
/* Ignore GPE1 block by setting the register count to zero */
register_count1 = 0;
}
else {
/* Install GPE Block 1 */
status =
acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
address,
acpi_gbl_FADT.xgpe1_block.
space_id, register_count1,
acpi_gbl_FADT.gpe1_base,
acpi_gbl_FADT.
sci_interrupt,
&acpi_gbl_gpe_fadt_blocks
[1]);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"Could not create GPE Block 1"));
}
/*
* GPE0 and GPE1 do not have to be contiguous in the GPE number
* space. However, GPE0 always starts at GPE number zero.
*/
}
}
/* Exit if there are no GPE registers */
if ((register_count0 + register_count1) == 0) {
/* GPEs are not required by ACPI, this is OK */
ACPI_DEBUG_PRINT((ACPI_DB_INIT,
"There are no GPE blocks defined in the FADT\n"));
goto cleanup;
}
cleanup:
(
void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_update_gpes
*
* PARAMETERS: table_owner_id - ID of the newly-loaded ACPI table
*
* RETURN: None
*
* DESCRIPTION: Check for new GPE methods (_Lxx/_Exx) made available as a
* result of a Load() or load_table() operation. If new GPE
* methods have been installed, register the new methods.
*
******************************************************************************/
void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
{
struct acpi_gpe_xrupt_info *gpe_xrupt_info;
struct acpi_gpe_block_info *gpe_block;
struct acpi_gpe_walk_info walk_info;
acpi_status status = AE_OK;
/*
* Find any _Lxx/_Exx GPE methods that have just been loaded.
*
* Any GPEs that correspond to new _Lxx/_Exx methods are immediately
* enabled.
*
* Examine the namespace underneath each gpe_device within the
* gpe_block lists.
*/
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return;
}
walk_info.count = 0;
walk_info.owner_id = table_owner_id;
walk_info.execute_by_owner_id =
TRUE;
/* Walk the interrupt level descriptor list */
gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
while (gpe_xrupt_info) {
/* Walk all Gpe Blocks attached to this interrupt level */
gpe_block = gpe_xrupt_info->gpe_block_list_head;
while (gpe_block) {
walk_info.gpe_block = gpe_block;
walk_info.gpe_device = gpe_block->node;
status = acpi_ns_walk_namespace(ACPI_TYPE_METHOD,
walk_info.gpe_device,
ACPI_UINT32_MAX,
ACPI_NS_WALK_NO_UNLOCK,
acpi_ev_match_gpe_method,
NULL, &walk_info, NULL);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"While decoding _Lxx/_Exx methods"));
}
gpe_block = gpe_block->next;
}
gpe_xrupt_info = gpe_xrupt_info->next;
}
if (walk_info.count) {
ACPI_INFO((
"Enabled %u new GPEs", walk_info.count));
}
(
void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return;
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_match_gpe_method
*
* PARAMETERS: Callback from walk_namespace
*
* RETURN: Status
*
* DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
* control method under the _GPE portion of the namespace.
* Extract the name and GPE type from the object, saving this
* information for quick lookup during GPE dispatch. Allows a
* per-owner_id evaluation if execute_by_owner_id is TRUE in the
* walk_info parameter block.
*
* The name of each GPE control method is of the form:
* "_Lxx" or "_Exx", where:
* L - means that the GPE is level triggered
* E - means that the GPE is edge triggered
* xx - is the GPE number [in HEX]
*
* If walk_info->execute_by_owner_id is TRUE, we only execute examine GPE methods
* with that owner.
*
******************************************************************************/
acpi_status
acpi_ev_match_gpe_method(acpi_handle obj_handle,
u32 level,
void *context,
void **return_value)
{
struct acpi_namespace_node *method_node =
ACPI_CAST_PTR(
struct acpi_namespace_node, obj_handle);
struct acpi_gpe_walk_info *walk_info =
ACPI_CAST_PTR(
struct acpi_gpe_walk_info, context);
struct acpi_gpe_event_info *gpe_event_info;
acpi_status status;
u32 gpe_number;
u8 temp_gpe_number;
char name[ACPI_NAMESEG_SIZE + 1];
u8 type;
ACPI_FUNCTION_TRACE(ev_match_gpe_method);
/* Check if requested owner_id matches this owner_id */
if ((walk_info->execute_by_owner_id) &&
(method_node->owner_id != walk_info->owner_id)) {
return_ACPI_STATUS(AE_OK);
}
/*
* Match and decode the _Lxx and _Exx GPE method names
*
* 1) Extract the method name and null terminate it
*/
ACPI_MOVE_32_TO_32(name, &method_node->name.integer);
name[ACPI_NAMESEG_SIZE] = 0;
/* 2) Name must begin with an underscore */
if (name[0] !=
'_') {
return_ACPI_STATUS(AE_OK);
/* Ignore this method */
}
/*
* 3) Edge/Level determination is based on the 2nd character
* of the method name
*/
switch (name[1]) {
case 'L':
type = ACPI_GPE_LEVEL_TRIGGERED;
break;
case 'E':
type = ACPI_GPE_EDGE_TRIGGERED;
break;
default:
/* Unknown method type, just ignore it */
ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
"Ignoring unknown GPE method type: %s "
"(name not of form _Lxx or _Exx)", name));
return_ACPI_STATUS(AE_OK);
}
/* 4) The last two characters of the name are the hex GPE Number */
status = acpi_ut_ascii_to_hex_byte(&name[2], &temp_gpe_number);
if (ACPI_FAILURE(status)) {
/* Conversion failed; invalid method, just ignore it */
ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
"Could not extract GPE number from name: %s "
"(name is not of form _Lxx or _Exx)", name));
return_ACPI_STATUS(AE_OK);
}
/* Ensure that we have a valid GPE number for this GPE block */
gpe_number = (u32)temp_gpe_number;
gpe_event_info =
acpi_ev_low_get_gpe_info(gpe_number, walk_info->gpe_block);
if (!gpe_event_info) {
/*
* This gpe_number is not valid for this GPE block, just ignore it.
* However, it may be valid for a different GPE block, since GPE0
* and GPE1 methods both appear under \_GPE.
*/
return_ACPI_STATUS(AE_OK);
}
if ((ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
ACPI_GPE_DISPATCH_HANDLER) ||
(ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
ACPI_GPE_DISPATCH_RAW_HANDLER)) {
/* If there is already a handler, ignore this GPE method */
return_ACPI_STATUS(AE_OK);
}
if (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags) ==
ACPI_GPE_DISPATCH_METHOD) {
/*
* If there is already a method, ignore this method. But check
* for a type mismatch (if both the _Lxx AND _Exx exist)
*/
if (type != (gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK)) {
ACPI_ERROR((AE_INFO,
"For GPE 0x%.2X, found both _L%2.2X and _E%2.2X methods",
gpe_number, gpe_number, gpe_number));
}
return_ACPI_STATUS(AE_OK);
}
/* Disable the GPE in case it's been enabled already. */
(
void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
/*
* Add the GPE information from above to the gpe_event_info block for
* use during dispatch of this GPE.
*/
gpe_event_info->flags &= ~(ACPI_GPE_DISPATCH_MASK);
gpe_event_info->flags |= (u8)(type | ACPI_GPE_DISPATCH_METHOD);
gpe_event_info->dispatch.method_node = method_node;
walk_info->count++;
ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
"Registered GPE method %s as GPE number 0x%.2X\n",
name, gpe_number));
return_ACPI_STATUS(AE_OK);
}
#endif /* !ACPI_REDUCED_HARDWARE */
