path: root/drivers/acpi/acpica/tbdata.c

// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
 *
 * Module Name: tbdata - Table manager data structure functions
 *
 * Copyright (C) 2000 - 2025, Intel Corp.
 *
 *****************************************************************************/

#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "actables.h"
#include "acevents.h"

#define _COMPONENT          ACPI_TABLES
ACPI_MODULE_NAME("tbdata")

/* Local prototypes */
static acpi_status
acpi_tb_check_duplication(struct acpi_table_desc *table_desc, u32 *table_index);

static u8
acpi_tb_compare_tables(struct acpi_table_desc *table_desc, u32 table_index);

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_compare_tables
 *
 * PARAMETERS:  table_desc          - Table 1 descriptor to be compared
 *              table_index         - Index of table 2 to be compared
 *
 * RETURN:      TRUE if both tables are identical.
 *
 * DESCRIPTION: This function compares a table with another table that has
 *              already been installed in the root table list.
 *
 ******************************************************************************/

static u8
acpi_tb_compare_tables(struct acpi_table_desc *table_desc, u32 table_index)
{
	acpi_status status = AE_OK;
	u8 is_identical;
	struct acpi_table_header *table;
	u32 table_length;
	u8 table_flags;

	status =
	    acpi_tb_acquire_table(&acpi_gbl_root_table_list.tables[table_index],
				  &table, &table_length, &table_flags);
	if (ACPI_FAILURE(status)) {
		return (FALSE);
	}

	/*
	 * Check for a table match on the entire table length,
	 * not just the header.
	 */
	is_identical = (u8)((table_desc->length != table_length ||
			     memcmp(table_desc->pointer, table, table_length)) ?
			    FALSE : TRUE);

	/* Release the acquired table */

	acpi_tb_release_table(table, table_length, table_flags);
	return (is_identical);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_init_table_descriptor
 *
 * PARAMETERS:  table_desc              - Table descriptor
 *              address                 - Physical address of the table
 *              flags                   - Allocation flags of the table
 *              table                   - Pointer to the table
 *
 * RETURN:      None
 *
 * DESCRIPTION: Initialize a new table descriptor
 *
 ******************************************************************************/

void
acpi_tb_init_table_descriptor(struct acpi_table_desc *table_desc,
			      acpi_physical_address address,
			      u8 flags, struct acpi_table_header *table)
{

	/*
	 * Initialize the table descriptor. Set the pointer to NULL for external
	 * tables, since the table is not fully mapped at this time.
	 */
	memset(table_desc, 0, sizeof(struct acpi_table_desc));
	table_desc->address = address;
	table_desc->length = table->length;
	table_desc->flags = flags;
	ACPI_MOVE_32_TO_32(table_desc->signature.ascii, table->signature);

	switch (table_desc->flags & ACPI_TABLE_ORIGIN_MASK) {
	case ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL:
	case ACPI_TABLE_ORIGIN_EXTERNAL_VIRTUAL:

		table_desc->pointer = table;
		break;

	case ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL:
	default:

		break;
	}
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_acquire_table
 *
 * PARAMETERS:  table_desc          - Table descriptor
 *              table_ptr           - Where table is returned
 *              table_length        - Where table length is returned
 *              table_flags         - Where table allocation flags are returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Acquire an ACPI table. It can be used for tables not
 *              maintained in the acpi_gbl_root_table_list.
 *
 ******************************************************************************/

acpi_status
acpi_tb_acquire_table(struct acpi_table_desc *table_desc,
		      struct acpi_table_header **table_ptr,
		      u32 *table_length, u8 *table_flags)
{
	struct acpi_table_header *table = NULL;

	switch (table_desc->flags & ACPI_TABLE_ORIGIN_MASK) {
	case ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL:

		table =
		    acpi_os_map_memory(table_desc->address, table_desc->length);
		break;

	case ACPI_TABLE_ORIGIN_INTERNAL_VIRTUAL:
	case ACPI_TABLE_ORIGIN_EXTERNAL_VIRTUAL:

		table = table_desc->pointer;
		break;

	default:

		break;
	}

	/* Table is not valid yet */

	if (!table) {
		return (AE_NO_MEMORY);
	}

	/* Fill the return values */

	*table_ptr = table;
	*table_length = table_desc->length;
	*table_flags = table_desc->flags;
	return (AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_tb_release_table
 *
 * PARAMETERS:  table               - Pointer for the table
 *              table_length        - Length for the table
 *              table_flags         - Allocation flags for the table
 *
 * RETURN:      None
 *
 * D