/*
* Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <errno.h>
#include <ipxe/acpi.h>
#include <ipxe/interface.h>
/** @file
*
* ACPI support functions
*
*/
/******************************************************************************
*
* Utility functions
*
******************************************************************************
*/
/**
* Fix up ACPI table checksum
*
* @v acpi ACPI table header
*/
void acpi_fix_checksum ( struct acpi_description_header *acpi ) {
unsigned int i = 0;
uint8_t sum = 0;
for ( i = 0 ; i < acpi->length ; i++ ) {
sum += *( ( ( uint8_t * ) acpi ) + i );
}
acpi->checksum -= sum;
}
/******************************************************************************
*
* Interface methods
*
******************************************************************************
*/
/**
* Describe object in an ACPI table
*
* @v intf Interface
* @v acpi ACPI table
* @v len Length of ACPI table
* @ret rc Return status code
*/
int acpi_describe ( struct interface *intf,
struct acpi_description_header *acpi, size_t len ) {
struct interface *dest;
acpi_describe_TYPE ( void * ) *op =
intf_get_dest_op ( intf, acpi_describe, &dest );
void *object = intf_object ( dest );
int rc;
if ( op ) {
rc = op ( object, acpi, len );
} else {
/* Default is to fail to describe */
rc = -EOPNOTSUPP;
}
intf_put ( dest );
return rc;
}