https://github.com/torvalds/linux
Tip revision: f443e374ae131c168a065ea1748feac6b2e76613 authored by Linus Torvalds on 20 March 2022, 20:14:17 UTC
Linux 5.17
Linux 5.17
Tip revision: f443e37
tbxface.c
// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: tbxface - ACPI table-oriented external interfaces
*
* Copyright (C) 2000 - 2021, Intel Corp.
*
*****************************************************************************/
#define EXPORT_ACPI_INTERFACES
#include <acpi/acpi.h>
#include "accommon.h"
#include "actables.h"
#define _COMPONENT ACPI_TABLES
ACPI_MODULE_NAME("tbxface")
/*******************************************************************************
*
* FUNCTION: acpi_allocate_root_table
*
* PARAMETERS: initial_table_count - Size of initial_table_array, in number of
* struct acpi_table_desc structures
*
* RETURN: Status
*
* DESCRIPTION: Allocate a root table array. Used by iASL compiler and
* acpi_initialize_tables.
*
******************************************************************************/
acpi_status acpi_allocate_root_table(u32 initial_table_count)
{
acpi_gbl_root_table_list.max_table_count = initial_table_count;
acpi_gbl_root_table_list.flags = ACPI_ROOT_ALLOW_RESIZE;
return (acpi_tb_resize_root_table_list());
}
/*******************************************************************************
*
* FUNCTION: acpi_initialize_tables
*
* PARAMETERS: initial_table_array - Pointer to an array of pre-allocated
* struct acpi_table_desc structures. If NULL, the
* array is dynamically allocated.
* initial_table_count - Size of initial_table_array, in number of
* struct acpi_table_desc structures
* allow_resize - Flag to tell Table Manager if resize of
* pre-allocated array is allowed. Ignored
* if initial_table_array is NULL.
*
* RETURN: Status
*
* DESCRIPTION: Initialize the table manager, get the RSDP and RSDT/XSDT.
*
* NOTE: Allows static allocation of the initial table array in order
* to avoid the use of dynamic memory in confined environments
* such as the kernel boot sequence where it may not be available.
*
* If the host OS memory managers are initialized, use NULL for
* initial_table_array, and the table will be dynamically allocated.
*
******************************************************************************/
acpi_status ACPI_INIT_FUNCTION
acpi_initialize_tables(struct acpi_table_desc *initial_table_array,
u32 initial_table_count, u8 allow_resize)
{
acpi_physical_address rsdp_address;
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_initialize_tables);
/*
* Setup the Root Table Array and allocate the table array
* if requested
*/
if (!initial_table_array) {
status = acpi_allocate_root_table(initial_table_count);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
} else {
/* Root Table Array has been statically allocated by the host */
memset(initial_table_array, 0,
(acpi_size)initial_table_count *
sizeof(struct acpi_table_desc));
acpi_gbl_root_table_list.tables = initial_table_array;
acpi_gbl_root_table_list.max_table_count = initial_table_count;
acpi_gbl_root_table_list.flags = ACPI_ROOT_ORIGIN_UNKNOWN;
if (allow_resize) {
acpi_gbl_root_table_list.flags |=
ACPI_ROOT_ALLOW_RESIZE;
}
}
/* Get the address of the RSDP */
rsdp_address = acpi_os_get_root_pointer();
if (!rsdp_address) {
return_ACPI_STATUS(AE_NOT_FOUND);
}
/*
* Get the root table (RSDT or XSDT) and extract all entries to the local
* Root Table Array. This array contains the information of the RSDT/XSDT
* in a common, more usable format.
*/
status = acpi_tb_parse_root_table(rsdp_address);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL_INIT(acpi_initialize_tables)
/*******************************************************************************
*
* FUNCTION: acpi_reallocate_root_table
*
* PARAMETERS: None
*
* RETURN: Status
*
* DESCRIPTION: Reallocate Root Table List into dynamic memory. Copies the
* root list from the previously provided scratch area. Should
* be called once dynamic memory allocation is available in the
* kernel.
*
******************************************************************************/
acpi_status ACPI_INIT_FUNCTION acpi_reallocate_root_table(void)
{
acpi_status status;
struct acpi_table_desc *table_desc;
u32 i, j;
ACPI_FUNCTION_TRACE(acpi_reallocate_root_table);
/*
* If there are tables unverified, it is required to reallocate the
* root table list to clean up invalid table entries. Otherwise only
* reallocate the root table list if the host provided a static buffer
* for the table array in the call to acpi_initialize_tables().
*/
if ((acpi_gbl_root_table_list.flags & ACPI_ROOT_ORIGIN_ALLOCATED) &&
acpi_gbl_enable_table_validation) {
return_ACPI_STATUS(AE_SUPPORT);
}
(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
/*
* Ensure OS early boot logic, which is required by some hosts. If the
* table state is reported to be wrong, developers should fix the
* issue by invoking acpi_put_table() for the reported table during the
* early stage.
*/
for (i = 0; i < acpi_gbl_root_table_list.current_table_count; ++i) {
table_desc = &acpi_gbl_root_table_list.tables[i];
if (table_desc->pointer) {
ACPI_ERROR((AE_INFO,
"Table [%4.4s] is not invalidated during early boot stage",
table_desc->signature.ascii));
}
}
if (!acpi_gbl_enable_table_validation) {
/*
* Now it's safe to do full table validation. We can do deferred
* table initialization here once the flag is set.
*/
acpi_gbl_enable_table_validation = TRUE;
for (i = 0; i < acpi_gbl_root_table_list.current_table_count;
++i) {
table_desc = &acpi_gbl_root_table_list.tables[i];
if (!(table_desc->flags & ACPI_TABLE_IS_VERIFIED)) {
status =
acpi_tb_verify_temp_table(table_desc, NULL,
&j);
if (ACPI_FAILURE(status)) {
acpi_tb_uninstall_table(table_desc);
}
}
}
}
acpi_gbl_root_table_list.flags |= ACPI_ROOT_ALLOW_RESIZE;
status = acpi_tb_resize_root_table_list();
acpi_gbl_root_table_list.flags |= ACPI_ROOT_ORIGIN_ALLOCATED;
(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL_INIT(acpi_reallocate_root_table)
/*******************************************************************************
*
* FUNCTION: acpi_get_table_header
*
* PARAMETERS: signature - ACPI signature of needed table
* instance - Which instance (for SSDTs)
* out_table_header - The pointer to the where the table header
* is returned
*
* RETURN: Status and a copy of the table header
*
* DESCRIPTION: Finds and returns an ACPI table header. Caller provides the
* memory where a copy of the header is to be returned
* (fixed length).
*
******************************************************************************/
acpi_status
acpi_get_table_header(char *signature,
u32 instance, struct acpi_table_header *out_table_header)
{
u32 i;
u32 j;
struct acpi_table_header *header;
/* Parameter validation */
if (!signature || !out_table_header) {
return (AE_BAD_PARAMETER);
}
/* Walk the root table list */
for (i = 0, j = 0; i < acpi_gbl_root_table_list.current_table_count;
i++) {
if (!ACPI_COMPARE_NAMESEG
(&(acpi_gbl_root_table_list.tables[i].signature),
signature)) {
continue;
}
if (++j < instance) {
continue;
}
if (!acpi_gbl_root_table_list.tables[i].pointer) {
if ((acpi_gbl_root_table_list.tables[i].flags &
ACPI_TABLE_ORIGIN_MASK) ==
ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL) {
header =
acpi_os_map_memory(acpi_gbl_root_table_list.
tables[i].address,
sizeof(struct
acpi_table_header));
if (!header) {
return (AE_NO_MEMORY);
}
memcpy(out_table_header, header,
sizeof(struct acpi_table_header));
acpi_os_unmap_memory(header,
sizeof(struct
acpi_table_header));
} else {
return (AE_NOT_FOUND);
}
} else {
memcpy(out_table_header,
acpi_gbl_root_table_list.tables[i].pointer,
sizeof(struct acpi_table_header));
}
return (AE_OK);
}
return (AE_NOT_FOUND);
}
ACPI_EXPORT_SYMBOL(acpi_get_table_header)
/*******************************************************************************
*
* FUNCTION: acpi_get_table
*
* PARAMETERS: signature - ACPI signature of needed table
* instance - Which instance (for SSDTs)
* out_table - Where the pointer to the table is returned
*
* RETURN: Status and pointer to the requested table
*
* DESCRIPTION: Finds and verifies an ACPI table. Table must be in the
* RSDT/XSDT.
* Note that an early stage acpi_get_table() call must be paired
* with an early stage acpi_put_table() call. otherwise the table
* pointer mapped by the early stage mapping implementation may be
* erroneously unmapped by the late stage unmapping implementation
* in an acpi_put_table() invoked during the late stage.
*
******************************************************************************/
acpi_status
acpi_get_table(char *signature,
u32 instance, struct acpi_table_header ** out_table)
{
u32 i;
u32 j;
acpi_status status = AE_NOT_FOUND;
struct acpi_table_desc *table_desc;
/* Parameter validation */
if (!signature || !out_table) {
return (AE_BAD_PARAMETER);
}
/*
* Note that the following line is required by some OSPMs, they only
* check if the returned table is NULL instead of the returned status
* to determined if this function is succeeded.
*/
*out_table = NULL;
(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
/* Walk the root table list */
for (i = 0, j = 0; i < acpi_gbl_root_table_list.current_table_count;
i++) {
table_desc = &acpi_gbl_root_table_list.tables[i];
if (!ACPI_COMPARE_NAMESEG(&table_desc->signature, signature)) {
continue;
}
if (++j < instance) {
continue;
}
status = acpi_tb_get_table(table_desc, out_table);
break;
}
(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_get_table)
/*******************************************************************************
*
* FUNCTION: acpi_put_table
*
* PARAMETERS: table - The pointer to the table
*
* RETURN: None
*
* DESCRIPTION: Release a table returned by acpi_get_table() and its clones.
* Note that it is not safe if this function was invoked after an
* uninstallation happened to the original table descriptor.
* Currently there is no OSPMs' requirement to handle such
* situations.
*
******************************************************************************/
void acpi_put_table(struct acpi_table_header *table)
{
u32 i;
struct acpi_table_desc *table_desc;
ACPI_FUNCTION_TRACE(acpi_put_table);
if (!table) {
return_VOID;
}
(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
/* Walk the root table list */
for (i = 0; i < acpi_gbl_root_table_list.current_table_count; i++) {
table_desc = &acpi_gbl_root_table_list.tables[i];
if (table_desc->pointer != table) {
continue;
}
acpi_tb_put_table(table_desc);
break;
}
(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
return_VOID;
}
ACPI_EXPORT_SYMBOL(acpi_put_table)
/*******************************************************************************
*
* FUNCTION: acpi_get_table_by_index
*
* PARAMETERS: table_index - Table index
* out_table - Where the pointer to the table is returned
*
* RETURN: Status and pointer to the requested table
*
* DESCRIPTION: Obtain a table by an index into the global table list. Used
* internally also.
*
******************************************************************************/
acpi_status
acpi_get_table_by_index(u32 table_index, struct acpi_table_header **out_table)
{
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_get_table_by_index);
/* Parameter validation */
if (!out_table) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/*
* Note that the following line is required by some OSPMs, they only
* check if the returned table is NULL instead of the returned status
* to determined if this function is succeeded.
*/
*out_table = NULL;
(void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);
/* Validate index */
if (table_index >= acpi_gbl_root_table_list.current_table_count) {
status = AE_BAD_PARAMETER;
goto unlock_and_exit;
}
status =
acpi_tb_get_table(&acpi_gbl_root_table_list.tables[table_index],
out_table);
unlock_and_exit:
(void)acpi_ut_release_mutex(ACPI_MTX_TABLES);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_get_table_by_index)
/*******************************************************************************
*
* FUNCTION: acpi_install_table_handler
*
* PARAMETERS: handler - Table event handler
* context - Value passed to the handler on each event
*
* RETURN: Status
*
* DESCRIPTION: Install a global table event handler.
*
******************************************************************************/
acpi_status
acpi_install_table_handler(acpi_table_handler handler, void *context)
{
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_install_table_handler);
if (!handler) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Don't allow more than one handler */
if (acpi_gbl_table_handler) {
status = AE_ALREADY_EXISTS;
goto cleanup;
}
/* Install the handler */
acpi_gbl_table_handler = handler;
acpi_gbl_table_handler_context = context;
cleanup:
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_install_table_handler)
/*******************************************************************************
*
* FUNCTION: acpi_remove_table_handler
*
* PARAMETERS: handler - Table event handler that was installed
* previously.
*
* RETURN: Status
*
* DESCRIPTION: Remove a table event handler
*
******************************************************************************/
acpi_status acpi_remove_table_handler(acpi_table_handler handler)
{
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_remove_table_handler);
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Make sure that the installed handler is the same */
if (!handler || handler != acpi_gbl_table_handler) {
status = AE_BAD_PARAMETER;
goto cleanup;
}
/* Remove the handler */
acpi_gbl_table_handler = NULL;
cleanup:
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_remove_table_handler)