linux/drivers/acpi/acpica/evgpeinit.c
Rafael J. Wysocki 7a8379eb41 ACPICA: Add support for using logical addresses of GPE blocks
The logical address of every GPE block in system memory must be
known before passing it to acpi_ev_initialize_gpe_block(), because
memory cannot be mapped on the fly from an interrupt handler.
Accordingly, the host OS must map every GPE block in system
memory upfront and it can store the logical addresses of GPE
blocks for future use.

If these logical addresses were known to ACPICA, it could use them
instead of the corresponding physical addresses of GPE block for
GPE register accesses and the memory mapping lookups carried out
by acpi_os_read_memory() and acpi_os_write_memory() on every
attempt to access a GPE register would not be necessary any more.

To allow that to happen, introduce the ACPI_GPE_USE_LOGICAL_ADDRESSES
symbol to indicate whether or not the host OS wants ACPICA to use the
logical addresses of GPE registers in system memory directly (which
is the case if this symbol is defined).  Moreover, conditional on
whether ACPI_GPE_USE_LOGICAL_ADDRESSES is defined, introduce two new
global variables for storing the logical addresses of the FADT GPE
blocks 0 and 1, respectively, acpi_gbl_xgpe0_block_logical_address and
acpi_gbl_xgpe1_block_logical_address, make acpi_ev_gpe_initialize()
pass their values instead of the physical addresses of the GPE blocks
in question to acpi_ev_create_gpe_block() and modify
acpi_hw_gpe_read() and acpi_hw_gpe_write() to access memory directly
via the addresses stored in the struct acpi_gpe_address objects,
which are expected to be the logical addresses of GPE registers if
ACPI_GPE_USE_LOGICAL_ADDRESSES is defined.

With the above changes in place, a host OS wanting ACPICA to
access GPE registers directly through their logical addresses
needs to define the ACPI_GPE_USE_LOGICAL_ADDRESSES symbol and
make sure that the logical addresses of the FADT GPE blocks 0
and 1 are stored in acpi_gbl_xgpe0_block_logical_address and
acpi_gbl_xgpe1_block_logical_address, respectively, prior to
calling acpi_ev_gpe_initialize().

[If such a host OS also uses acpi_install_gpe_block() to add
 non-FADT GPE register blocks located in system memory, it must
 pass their logical addresses instead of their physical addresses
 to this function.]

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-09-11 16:44:45 +02:00

424 lines
12 KiB
C

// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: evgpeinit - System GPE initialization and update
*
* Copyright (C) 2000 - 2020, 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;
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 */