linux/drivers/acpi/acpica/utcksum.c

// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
 *
 * Module Name: utcksum - Support generating table checksums
 *
 * Copyright (C) 2000 - 2023, Intel Corp.
 *
 *****************************************************************************/

#include <acpi/acpi.h>
#include "accommon.h"
#include "acutils.h"

/* This module used for application-level code only */

#define _COMPONENT …
ACPI_MODULE_NAME("utcksum")

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_verify_checksum
 *
 * PARAMETERS:  table               - ACPI table to verify
 *              length              - Length of entire table
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns
 *              exception on bad checksum.
 *              Note: We don't have to check for a CDAT here, since CDAT is
 *              not in the RSDT/XSDT, and the CDAT table is never installed
 *              via ACPICA.
 *
 ******************************************************************************/
acpi_status acpi_ut_verify_checksum(struct acpi_table_header *table, u32 length)
{ … }

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_verify_cdat_checksum
 *
 * PARAMETERS:  table               - CDAT ACPI table to verify
 *              length              - Length of entire table
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Verifies that the CDAT table checksums to zero. Optionally
 *              returns an exception on bad checksum.
 *
 ******************************************************************************/

acpi_status
acpi_ut_verify_cdat_checksum(struct acpi_table_cdat *cdat_table, u32 length)
{ … }

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_generate_checksum
 *
 * PARAMETERS:  table               - Pointer to table to be checksummed
 *              length              - Length of the table
 *              original_checksum   - Value of the checksum field
 *
 * RETURN:      8 bit checksum of buffer
 *
 * DESCRIPTION: Computes an 8 bit checksum of the table.
 *
 ******************************************************************************/

u8 acpi_ut_generate_checksum(void *table, u32 length, u8 original_checksum)
{ … }

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_checksum
 *
 * PARAMETERS:  buffer          - Pointer to memory region to be checked
 *              length          - Length of this memory region
 *
 * RETURN:      Checksum (u8)
 *
 * DESCRIPTION: Calculates circular checksum of memory region.
 *
 ******************************************************************************/

u8 acpi_ut_checksum(u8 *buffer, u32 length)
{ … }